Technology today can be used to track users across domains. A study in 2009 saw Google on 92 of the top 100 sites followed by DoubleClick with 70 presences (which are now also Google owned) and Microsoft’s Atlas with 60 occurrences.

Cookies, regular or Flash, are usually used to track users. These cookies can be accessed on all domains a company script is loaded on, which in the case of Google would mean the ability to track user movement on 92 of the top 100 domains in the world. While this percentage is surely going down a bit if the sample size increases, it is still common to be tracked across many web properties.

There are options available to not be tracked online. This includes clearing all cookies after or even during a browsing session, using private browsing modes, or installing extensions like the excellent NoScript to block third party scripts from running on a site.

TrackerBlock, available for Firefox, Internet Explorer and Google Chrome offers another option. The program can make sure that you are not tracked across the web. It does so in a number of ways:

• Do Not Track Me Header – Whenever you make a request to a website, you submit a signal that tells the website that you do not want your activities tracked. Websites and companies are not obligated though. Option to delete Flash cookies.
• Opt-Out Cookies – So called opt-out cookies tell websites, services and agencies that the user does not want to be tracked. This turns off data collection and tracking off more than one hundred companies.
• Tracker Blocking – Blocks advertising agencies and companies from reading or writing cookies on your system. The extension does that for more than 550 different companies.
• HTML5 Storage – Visualizes which companies are using HTML5 to store data on your system, with options to delete the data manually.

Click on an image to see how the settings and preferences look like in the Firefox web browser.

The program combines several anti-tracking options in one interface. Especially useful is the ability to write the opt-out cookies on the system, to clear Flash and HTML5 data storage that are often used for tracking, and to block advertising companies from reading or writing cookies on the system.

TrackerBlock can best be installed at the Privacy Choice website, as it is available there for all supported browsers. It is not really clear if the extension is available for other browsers as well. It is definitely available for Firefox, Chrome and Internet Explorer.

Google Chrome users can clear all browsing data, which includes cookies but also other data like the browsing and download history, by clicking on the wrench icon in the toolbar and selecting Tools > Clear Browsing Data from the menu that pops up.

It is alternatively possible to use the keyboard shortcut Ctrl-Shift-Del for the same effect. A window is displayed where the data can be cleared.

Please note that there is a link to the Adobe Flash Player storage settings. If you click on that link you will be taken to Adobe’s Website Storage Settings panel where you can delete all or select Flash cookies.

If you go back to the Chrome browser you may have noticed that the clear browsing data window does not offer to clear individual files. Sometimes you may want to delete a specific cookie or a set of cookies only. This can be handy for web developers testing a new site feature, users who accidentally visited a site and want to delete its traces or users who want to clear personalized data.

The easiest way to clear individual cookies in Google Chrome is to enter chrome://settings/cookies into the address bar. This opens the cookies and other data listing in the browser. All stored cookies are displayed here. It is possible to remove all cookies or search for individual cookies.

A click on a site displays all cookies stored by that site on the computer. It takes another click to display detailed information about the cookie and the Remove button. If you click on Remove the selected cookie will be deleted from the system.

And that’s how you delete standard and Flash cookies in the Chrome web browser individually.

Google Chrome Canary recently introduced the option to clear plug-in related temporary contents when clearing the browsing data, and it appears that Microsoft’s Internet Explorer will follow suit.

A recent post on the Internet Explorer blog highlights the change: Microsoft has added relevant APIS back when Microsoft Internet Explorer 8 was released. With Adobe’s implementation of the new controls in Flash Player 10.3, it is now possible to delete Flash Cookies directly in Internet Explorer.

Adobe is implementing the new controls in Flash Player 10.3 which is currently available as a release candidate. Users who want to clean Flash Cookies in Internet Explorer need to download and install the Flash Player 10.3 release candidate, but do not need to make direct changes to Internet Explorer. The final version of Adobe Flash Player 10.3 will be released in the near future.

Microsoft has created a demo page where users can test the new feature.

You can use the demo page to create a Flash Cookie which gets saved on your system. You can test that by pressing F5 or reloading the page with a click on the reload button. The page should echo the information that a Flash Cookie is stored on your system.

This Flash Cookie, along with all others, will be deleted if you delete Internet Explorer’s browsing history. You can delete the browsing history under Tools > Safety > Delete Browsing History. Please note that you need Adobe Flash Player 10.3 or newer for this to work.

Both Internet Explorer 8 and Internet Explorer 9 support the feature out of the box.

The demonstration page works flawlessly under Google Chrome as well, which means that Canary users can test their browser’s cookie cleaning functionality as well.

Other browser developers like Mozilla have already announced that they will integrate Flash Cookies cleaning in future browser versions as well.

It seems as if we are finally able to resolve the Flash Cookies problem once and for all.

It still means that you have to click on an extra link to open the settings before you can delete the additional objects in the Chrome browser, but that’s better than providing no link at all.

The latest build of Google Chrome Canary is showing improvements in this regard. It now offers the option to delete cookies and plug-in data natively without opening the Flash storage page after the initial local cleanup of temporary browsing data.

Flash cookies are often used by advertisers and marketing companies to track users on the Internet. This in addition to standard cookies. The core advantage of Flash cookies from a company’s point of view is that they are harder to access and delete on the user side which makes the tracking more effective.

This is now changing in Google Chrome with the inclusion of clearing plug-in data directly in the browser.

The standard “Adobe Flash Player storage settings link has been removed from the Clear Browsing Data.

The new feature is currently only available in the latest Chrome Canary builds. It is likely that it will be moved quickly to to be included in Dev, Beta and eventually Chrome stable builds.

The option to delete Flash cookies is enabled by default when a user clicks on the Clear browsing data button in the Chrome options. This suggests that more users will clear their Flash cookies from now on, at least in the Chrome browser. It could lead to some problems on the other hand, considering that Flash cookies are used by gaming sites to store high-scores and other information.

Chrome users can also use the shortcut Ctrl-Shift-Del to quickly open the Clear Browsing Data menu.

It is likely that the native integration of the Flash plugin in the Chrome browser has made that possible. (via Browser Scene)

You can get more information about Flash Cookies in a guide we have posted a few years ago. Adobe has now announced that they have plans to “LSO management with the browser UI” which would mean that users would be able to delete those cookies just like they are able to delete regular cookies.

Most recently, we’ve been collaborating with browser vendors to integrate LSO management with the browser UI. The first capability, one that we believe will have the greatest immediate impact, is to allow users to clear LSOs (and any local storage, such as that of HTML5 and other plugin technologies) from the browser settings interface—similar to how users can clear their browser cookies today. Representatives from several key companies, including Adobe, Mozilla and Google have been working together to define a new browser API (NPAPI ClearSiteData) for clearing local data, which was approved for implementation on January 5, 2011. Any browser that implements the API will be able to clear local storage for any plugin that also implements the API.

Adobe basically has created a new browser api which can be used by the browser to clear the local storage. This throws the ball to the browser developers who now need to evaluate if and how they can implement this new option in their browser.

Another interesting change is that Adobe wants to integrate Flash Player Settings Manager directly “Control Panels or System Preferences on Windows, Mac and Linux”. While that’s hopefully optional it will give users a direct easier way of accessing those settings.

The first browser to roll out with the new feature will be Google Chrome dev which may offer the feature in a few weeks.

Interested users find the full blog post over at the Adobe Blog.

One of the best options therefor is to use third party tools like CCleaner to clean data left by the web browser on the computer system.

The Firefox and Google Chrome add-on Click&Clean offers an alternative to third party tools by providing those features directly in the supported web browser.

The Google Chrome extension offers deeper configuration options than the Firefox add-on, the end result on the other hand can be the same (depending on the configuration).

Firefox Click&Clean Add-on

The options are divided into three groups. Clear private data will delete the web browsing data either directly when triggered manually or on browser exit. An external application can be integrated into the add-on so that it will be run as well. The advanced options finally allow the user to delete Flash Cookies from the system.

Google Chrome Click&Clean Extensions

The Chrome extension looks completely different and offers customization that the Firefox add-on does not offer.

A click on the items in the left sidebar opens in depth configuration options that include all clear browsing data options of the browser plus more. It is for instance possible to remove Flash cookies, Silverlight cookies, the Java cache, Google Gears data, extension local storage, cookies and SQL databases. There are even options to delete the recycle bin and temporary files of the operating system.

It is furthermore possible to configure when and how data is cleared with options to delete data manually or automatically. The option to launch an external application with arguments is available as well in Chrome.

That still is not everything that the Google Chrome extension has to offer. A click on the extension’s icon in the Chrome toolbar opens a menu with quick access to clearing the browsing data and new features like accessing the browser’s video history, memory usage and third party options like launching the system’s defragmenter or disk cleanup.

The Chrome extensions offers more than the Firefox add-on does. Both add-ons are available from the developer website and the official extension galleries on Mozilla.com and Google.com

What kind of traces are we talking about locally? Numerous if you are using the default settings of the browser, or browsers, you are using on the Internet. Probably the most known of them all are the web browser cache and cookies. The cache is filled with objects from websites that are accessed during sessions, and cookies are stored by the websites on the local system, either to track the user, save preferences or store login session information.

But there is more than that. There is the browsing history, possible downloads, browsing session information, Flash and Java plugin logs and temp files, Flash cookies, crash reports, data entered into search fields, offline cache or crash dumps. And even that may not be all.

Some web browsers offer means to clear at least some of the traces automatically. It is for instance possible to force the web browser to clear the web browsing cache, history and cookies on exit. But that’s not very efficient as it leaves lots of other traces behind.

Web Browsers Traces Eraser is a specialized tool that can be used to deal with web browsing traces of several popular browsers. The program supports the five popular web browsers Google Chrome, Internet Explorer, Mozilla Firefox, Opera and Apple Safari, but also lesser known browsers such as Flock, K-Melon, Avant Browser, Iron, Chrome Plus or SeaMonkey.

Cleaning options are displayed for each separately in the main interface. The program activates several web browsers by default that it identifies as being installed on the system. In addition to that, it offers to clear Flash Player Shared Objects, Flash Player Sys History, Java Cache, Java Logs, Java Temp Files and several Windows operating system traces. A click on Scan does the same during a session.

The clean button spawns a suggestion to create a System Restore point before the selected locations will be cleaned of all browsing traces. That’s recommended but optional. Settings can be saved, which is fine if you do not want to remove data from a certain web browser. These settings are however not loaded by default. It is necessary to either click on the Load button to load them, or to open the program’s settings to configure the program to load the settings ini file on startup.

Web Browsers Traces Eraser is more or less a specialized version of the popular temporary file cleaner CCleaner. Its main advantage is that it supports more web browsers out of the box than CCleaner. It lacks custom locations to include portable browsers and a preview of what is going to be cleaned before it is cleaned. There is also no option to whitelist cookies and other data.

The software program is available as a portable version and installer for the Windows operating system. Users who want to give it a try can download Web Browsers Traces Eraser from the No Virus Thanks website.

Evercookie takes this a step further by dropping as many cookies on the user’s system as possible. In particular, the Javascript API will make use of the following storage mechanisms if supported by the web browser.

• Standard HTTP Cookies
• Local Shared Objects (Flash Cookies)
• Silverlight Isolated Storage
• Storing cookies in RGB values of auto-generated, force-cached
• PNGs using HTML5 Canvas tag to read pixels (cookies) back out
• Storing cookies in Web History
• Storing cookies in HTTP ETags
• Storing cookies in Web cache
• window.name caching
• Internet Explorer userData storage
• HTML5 Session Storage
• HTML5 Local Storage
• HTML5 Global Storage
• HTML5 Database Storage via SQLite

Why would someone want to drop data into that many locations? Easy: For a far superior user identification. When a site drops a cookie on the user’s system it can identify the user for as long as the cookie is active. If the user deletes the cookie it cannot identify the user anymore. It may use algorithms to calculate probabilities but it usually cannot be sure that this is indeed a user who visited the site in the past.

Evercookies introduce a whole new level of user tracking. The website will be able to track the user, and reproduce deleted cookies, if at least one cookie or data in storage locations is not deleted by the user. And we all know that many users still have not heard about Flash cookies, the second most known form of storing cookies on a user system yet. How will those users cope with the news that there are more than ten additional ways of storing data to track a user?

Samy Kamkar has put up a demonstration page where users can set evercookies manually on their system. The same page contains options to rediscover the cookies. The suggested way of using the demonstration is to set the evercookie, delete cookies in all places known to the user to finally revisit the site to see if the evercookie is still existing on the system. The first rediscover button drops all deleted cookies in their place again, the second button does not do that. It is interesting that this method is able to track a user even if the browser is switched, at least as long as the Flash cookie is not deleted.

The JavaScript source is available on the page as well as a small FAQ. So what can you do to protect your system from this new kind of user tracking? Add-ons like NoScript prevent the creation of several of the cookies, as do Flash blockers (or no Flash at all on the system). Private browsing modes are an option as well.

The detection of third party cookies by security software does not mean that they pose the same danger as a computer virus, trojan or worm to the user. Tracking cookies are placed on the computer by online advertising companies. These companies track the user’s movement on the Internet for statistical and relevancy reasons.

One of the main purposes of cookies in general is to save temporary data, for instance language preferences or login information. Tracking cookies on the other hand are only created to track a users movement. The movement can still only be tracked if the user visits a website that displays the advertisement scripts of the company that has a cookie stored on the system.

Tracking cookies raise privacy issues, as they allow companies to partially track an Internet user’s movement on the Internet. The detected cookies can be deleted easily in the security software. Some web browsers, like Microsoft’s Internet Explorer, offer settings to handle third party cookies. The term third party cookies might confuse some users, but it is actually fairly easy to understand. A first party cookie is placed by the website itself, it would for instance be a first party cookie if Ghacks would place a cookie on your system. A third party cookie is placed by scripts from other services, mostly advertisements that are loaded on the page.

Internet Explorer

Internet Explorer users can clear all cookies in the web browser by clicking on Tools > Internet Options, and then the Delete button in the General tab. This opens the Delete Browsing History menu. Cookies is one of the items available in that menu. Keep in mind that this will delete all cookies, it may mean that certain site preferences are reset to their default values. It may also mean that a login prompt is displayed on some sites on the next connection.

internet explorer cookies

Cookies will be written again on the next connection. The third party cookie behavior can be configured in the Privacy tab of the Internet Options. The default setting is medium, which blocks some third party cookies but not all of them. Moving that slider to medium high, high or “block all cookies” will reduce or eliminate cookies in the web browser. A better approach, that blocks third party cookies completely, is to click on the Advanced button to open the Advanced Privacy Settings in Internet Explorer.

advanced privacy settings

Activate “Override automatic cookie handling” and change the third party cookie selection to Block. This blocks all third party cookies in Internet Explorer without affecting third party cookies at all.

Opera

Opera users can delete cookies by clicking on the Menu button at the top left of the web browser, and then Settings > Delete Private Data.

opera delete private data

A click on the Manage Cookies button after enabling detailed options in this menu lists all cookies with the option to delete them selectively instead.

Opera offers options to change the default cookie behavior and block tracking cookies. Press Ctrl-F12 to open the Opera Preferences. Switch to the Advanced tab and select cookies from the left sidebar menu.

Change Accept cookies to Accept cookies only from the site I visit to disable third party cookies in Opera.

opera block tracking cookies

Google Chrome

A click on the wrench and the selection of Options opens the Google Chrome Options window. The Under the Bonnet tab contains options to clear the browsing data and set the default cookie behavior.

A click on Clear browsing data opens a new window with the option to delete stored cookies, among other data.

delete cookies google chrome

General cookie behavior can be set in the Content settings menu. Cookies is one of the options in that menu. Locate the checkbox “Block all third-party cookies without exception” to block all tracking cookies from being set on the computer.

google chrome block tracking cookies

Mozilla Firefox

The keyboard shortcut Ctrl-Shift-Del opens the Clear Recent History menu in Firefox. Here it is possible to clear the cookies immediately.

clear recent history firefox

The Firefox options, located under Tools > Options offer controls to block third party cookies in the web browser. Locate the Privacy tab, and there the entry Accept third-party cookies. Remove the checkmark next to the preference to block tracking cookies and other third party cookies in the Firefox web browser.

firefox block third party cookies

Verdict

All popular web browsers offer controls to block third party cookies. Some advertising companies use Flash Cookies to track users. Please follow the link to the article linked above to find out how those can be deleted from the system as well.

The Adobe Flash player controls are web based controls for the Flash plugin that can be used to manage various Flash based parameters and Flash cookies.

Chrome users who only use the internal Flash plugin might have noticed that those web controls are not opening for them properly. The control area remains white with no option to show the controls in the web browser.

It took a while of searching to find a way to display the Flash player settings panel in Google Chrome. Open the Chrome options by clicking on the Tools button in the Chrome toolbar.

Switch to the Under the Bonnet tab and click the Content Settings button afterwards. Now click on the Adobe Flash Player storage settings link in the Cookies tab to open the Adobe Website Storage Settings panel that works in the Chrome browser.

This opens the Flash player controls correctly so that Google Chrome users can manage the Flash Player settings as well.

It is possible to open the url directly in Google Chrome so that it is not necessary to follow the menu path to open it.

The portable software Flash Cookies Cleaner is another program that can be used to quickly remove all flash cookies from a computer system.

The software program will automatically analyze the system and display all Flash cookies that it finds during the analysis in its interface.

A click on the Delete button will remove all Flash cookies from the PC. There is unfortunately no option to remove only selected cookies from the system.

Users who want to delete specific sites that have placed Flash cookies on the computer system need to use the Adobe web controls instead to do so. This is recommended for users who play online games or visit websites that save preferences and settings in Flash cookies.

Flash Cookies Cleaner can be downloaded from Softpedia.

Take a look at our Flash Cookies Explained article if you have not heard about this sort of cookies before, it will provide the overview needed.

Flash Cookies View will automatically display the flash cookies (also known as Local Shared Objects) that are stored on the computer system. Each Flash cookie is displayed in its own row that lists information that includes the originating url, file name, time the cookie was created and modified, the file size and file path.

The data can be sorted by each available column which makes it easier to locate specific contents. A search is provided as well to find cookies that contain the keywords entered in the search form.

The software program will display flash cookies that are stored in the default location of the operating system by default. It does however provide the option to change that default location to another path.

Selected items can be saved in a text document or added to an html report. It is furthermore possible to delete selected flash cookies and to change the display mode from cookie values to hex values.

Flash Cookies View is a portable software program for all supported Microsoft operating systems including Windows XP, Windows Vista and Windows 7. The program has been released yesterday and is available for download at the Nirsoft website.

We explained Flash Cookies in detail back in 2007 when a larger group of Internet users became aware of them. More than two years have passed since then with Flash cookies still playing a major role on many popular web services and for many advertising agencies.

Here are four options to deal with Flash cookies:

Option 1: Adobe Flash Player Settings

Probably the best option to deal with Flash cookies is to open the Adobe Flash Player settings. Users can look at the stored Flash cookies, delete some or all and change several options that change or even block Flash cookies on the user system.

Option 2: The manual way

Flash Cookies are stored on the local computer system. Their location varies depending on the operating system. Flash cookies are stored as *.sol files in the operating system. Here are the locations they can usually be found in:

• Windows: LSO files are stored typically with a “.SOL” extension, within each user’s Application Data directory, under Macromedia\Flash Player\#SharedObjects.
• Mac OS X: For Web sites, ~/Library/Preferences/Macromedia/Flash Player. For AIR Applications, ~/Library/Preferences/[package name (ID) of your app].
• GNU-Linux: ~/.macromedia, ~/.macromedia/Flash_Player/#SharedObjects, ~/.adobe

The process of deleting those flash cookies could be automated with the right software program, e.g. CCleaner for Windows.

Option 3: Firefox add-on Better Privacy

The Firefox add-on Better Privacy can delete Flash cookies regularly to get rid of them automatically with options to whitelist some Flash cookies that are needed, e.g. for storing high scores on your favorite gaming website or playback settings on Youtube.

Option 4: Flash Cookie Cleaner (Windows software)

Flash Cookie Cleaner is a software program for the Windows operating system. The portable software program can be used to delete all stored Flash cookies of the logged in user. It is available at the developer’s website.

This may however be not the only problem associated with private browsing. A recent paper by security researcher Kate McKinley confirms deficiencies in all web browsers and especially in Apple’s Safari. Not only normal cookie and data handling was tested but also plugin related handling of Flash and Google Gears data. The surprising result was that no browser passed all private browsing tests.

In fact, all of the existing private browsing modes have some form of data which is not cleared when users enter or leave private browsing modes. Although Chrome cleared the only tested type of data it stored, it was surprising to find that Gears data was not cleared, since Gears is included in the browser. However, this behavior is consistent across all browsers tested, as we will see later.

Firefox 3.1 Beta 2 clears cookies and session storage properly, but the persistent storage (window.globalStorage) is preserved between a normal and private browsing session.With IE 8 (Beta 2), both cookies and session storage were cleared properly, however the IE user Data stores were not cleared between the normal and private browsing sessions.

Safari on Windows fared the worst of all in these tests with respect to private browsing, and did not clear any data at all, either before entering or after exiting the private mode. On OSX, Safari’s behavior was quirky; in no case was the HTML 5 database storage cleared before or after private browsing. Previously set cookies seem to continue to be available if the user entered a private browsing session, but if the user started the browser and went directly into private browsing, it seemed to behave as expected.

All browsers have troubles with Flash Cookies and their private browsing modes. This is largely due to the way Flash Cookies are created and stored (without user interaction and means to display warnings). So what’s the conclusion in this matter? Users who like to use the private browsing mode should not use Apple’s Safari in its current stage. They should also make sure to either disable Flash and other third party plugins or use settings that prevent them from acting automatically (for example by using NoScript in Firefox).

Check out the Flash Cookies Explained article if you want to read up on Flash Cookies and find out where they are stored and how they can be deleted from a computer system.

Adobe is providing a website with options to change Flash Cookie behavior. Users can change the storage space – default 100K – or deny access to Flash Cookies to websites that they have already visited.

It’s not a practical solution though. Objection on the other hand is a Firefox add-on that is giving access to the Flash Cookies right in the browser. It is not possible to change settings with the add-on but it provides an easy way to delete selected (or all) Flash Cookies.

The add-on provides an automatic search to find the location of the Local Shared Objects Folder on the system. It was not able to detect mine and I had to manually add it by browsing to the correct location. According to Wikipedia Flash Cookies are located in..

• Windows: LSO files are stored typically with a “.SOL” extension, within each user’s Application Data directory, under Macromedia\Flash Player\#SharedObjects.
• Mac OS X: For Web sites, ~/Library/Preferences/Macromedia/Flash Player. For AIR Applications, ~/Library/Preferences/[package name (ID) of your app].
• GNU-Linux: ~/.macromedia

All Flash Cookies stored on the system are displayed once the folder has been correctly identified. A click on a Flash Cookie displays its contents. The user has the option to delete selected Flash Cookies only or all of them in one go.

Users can delete the cookies in that directory regularly or on a website. There is no direct way in Firefox to delete those cookies. That is, until now. The Firefox extension Better Privacy is a cookie manager for LSO Flash Objects and DOM Storage Objects. Flash Cookies (Local Shared Objects) are placed on the computer by a Flash application like the Youtube Video Player.

These cookies can be set to never expire which is obviously an excellent opportunity to track and analyze users. Another difference between flash and normal cookies is the size limitation. Normal cookies cannot exceed 4KB while Flash Cookies have a default size of 100 Kilobyte but the range is between 0 and Unlimited Kilobytes !

Better Privacy deletes Flash Cookies and DOM Storage cookies by deleting them on every startup. This setting can be changed to prevent the deletion of flash cookies that are needed. Several browser games make use of Flash cookies to save the progress of the player. The alternative option is to delete them manually in the options that are provided by the add-on.

Go to Youtube, increase or decrease the volume of the videos and delete all cookies afterwards. You will notice that the volume level is still at the same level when you close your browser and open it again. This is done with so called Local Shared Objects, better known as Flash cookies. The main question is of course how a computer can be checked for Flash cookies and how it would be possible to delete those cookies again.

This is actually a very tricky thing. I was searching for a way to check them on my computer but could not find it. After reading some information on the Adobe Flash Player website I was able to realize that the only possibility to check them was to open a page on the Adobe site which would show them.

The so called Settings Manager can be accessed from the Adobe website but is running locally on your computer. The Website Storage Settings display all Flash cookies that are currently saved on your computer. You can delete flash cookies from individual sites or all at once. It is also possible to increase or decrease the Kilobyte size of all information that are stored on your computer.

Adobe does not have access to the settings that you see in the Settings Manager or to personal information on your computer.

No Flash Cookies will be saved if you go into Global Storage Settings and disable the option “Allow third-party Flash content to store data on your computer”.

47 websites did store Flash cookies on my computer and I decided to delete all of them and disable the feature to be on the safe site. Did you know about Flash cookies ? How many did you find on your pc ?