Desktop email clients and security software often comes with an anti spam component as well to tackle spam on the desktop. That’s of no use for users who manage their email accounts on a website but those that prefer desktop software have additional anti spam software at their disposal to block spam from reaching the inbox.

The anti spam software Comodo AntiSpam is such a software program. It is compatible with many popular email clients such as Outlook, Windows Mail or Mozilla Thunderbird.

The anti spam software uses Passcode authentication to protect the email accounts from spam. This anti spam protection basically uses a whitelist of senders that are allowed to send email to the user. Every other email sender that is not in that list needs to reply to an email that are automatically generated before the original email will be accepted. It is like captcha for email.

The program walks the user through a five step setup process that consist of the following configurations:

• Generation of the passcode
• Import of authenticated senders either from email programs or address book files
• Configuration of email accounts that are automatically recognized by Comodo AntiSpam

Comodo AntiSpam runs in the background from that moment on. It will automatically send out the passcode email verifications to senders who are not on the authenticated sender list.

New email accounts can be added to the program at any time. It is furthermore possible to add email senders and domains to a blacklist so that their emails are blocked automatically from that time on.

How effective is Comodo AntiSpam? That depends on a number of factors. Spam is usually send out automated and a great deal of spam messages can be blocked with the passcode authentication. Spam senders who take the time to reply manually to the passcode authentication could however bypass the system. It is also likely that many phishing emails would go through as they fake the sender’s email address.

The verification raises concerns when it comes to first time contacts with legit companies as it is not clear how they will react if they receive a passcode reply email.

Comodo Antispam is nevertheless an interesting anti spam software that works best in addition to other anti spam techniques. The anti-spam software is available for free at the Comodo website.

Other concerns were that Akismet was not really a free anti spam plugin as webmasters who made more than $500 per month had to order a commercial version for $55 a year. The last concern was probably the most important one as data is send to Akismet servers including the commenter’s IP, user agent or referrer.

One of the main advantages of Antispam Bee is that it does not have to communicate with external servers for the anti spam protection. It is an all in one solution that detects spam not only in comments but also in trackbacks and pings.

The anti spam plugin runs out of the box after activation in the WordPress interface unlike Akismet which requires the WordPress api key. A few options of the free anti spam plugin can be configured in the WordPress settings. Antispam Bee will delete spam messages automatically when they are detected. This can be changed to mark them as spam and keep them for a limited time in the WordPress spam folder. Great for the first time of usage to monitor the performance of the anti spam software.

The main benefits of using Antispam Bee are twofold. It does increase the privacy of the users who comment on the blog as it does not submit data to third party servers which in turn reduces system resource usage which could be noticeable for blogs that receive many spam comments per day (Ghacks receives about a thousand a day).

We have been testing Antispam Bee for the last days and like the performance and spam detection rate a lot. Only one legit comment was flagged as spam by the anti spam plugin. Even better was the fact that comments from users who were usually flagged as spammers (jojo for example) were not moved to the spam folder at all.

Antispam Bee can be downloaded from the website of the developer. The WordPress plugin itself is multi-lingual (at least German and English).

Some plugins add specialized spam filters which is a great way of keeping spam messages from reaching your inbox. Other add statistics for instance that give you a better overview of the spam that has been captured so far. I’m not using Spamihilator anymore because I made the switch to Thunderbird which fights spam automatically.

A Blacklist Filter – This plugin checks mail messages against public blacklists.
Attachment Extensions Filter – Ability to block mails with attachments that have certain file extensions automatically
HTML Links Filter – blocks mails that contain to many links or urls
Misnamed filter – Blocks mail that is addressed to another name. So, mail saying Hello Robert will be moved to spam if your name is not Robert.
Mystic Signs Filter – Filters out mails that try to obscure words by integrating special chars into them.

The question that I’m asking myself is if you really need the Windows Defender if you have been using programs like ad-aware or spybot before and I think the answer is pretty obvious: No, Windows Defender is not needed. It might be fine for users who do not know and care about spyware and could help those users protect their computers in a more secure way from spyware and spam but everyone else should really stay with the program that they have been using before.

This is backed up by some tests, for instance by Suzi Turner from Zdnet, who used a virtual spyware infected system and tested the efficiency of Windows Defender. She came to the conclusion that Windows Defender was only able to detect 65% to 75% of the Spyware that was installed on the system compared to the commercial programs Spyware Doctor and Spyware Sweeper.

I personally think that Windows Defender is just another program that does not excel in what it should do. The same can be said for other softwares from Microsoft like the Windows Firewall for instance. I would advise everyone to either use other freely available tools to scan and protect your pc from spyware and spam or buy a commercial product that lives up to its promises. It is furthermore a good idea to test your system from time to time with a tool like Hijack This just to make sure nothing bypassed your anti-spyware program.

The traditional sending occurs either from local broadband connections or even from own server farms. Sending out 10 million spam mails that take up about 100 Gigabyteb of data takes up to five hours on a T3 connection.

The viral spammers use trojans and virii to infect other peoples computers and then send the mail from these instead of from their own connection. You might have heard that the dutch police recently captures three spammers who infected up to 1,5 million computers.

Update: So called bot networks are still a huge problem on today’s Internet. Using zombie PCs is a cost-effective way of sending spam messages to billions of users. Users new to the concept of Botnets should read the Wikipedia article on the topic for information on how botnets operate.

The Redtape Chronicles has published a 3-part series about botnets that makes another good read. It consists of the three parts “Is your computer a criminal”, “Virus gang warfare spills onto the net” and “Who’s behind criminal bot networks”.

It is a long read but well worth the time if you are interested in the topic.

Botnets back in 2007 were often between 50k and 70k PCs strong. The operators leased out the computing power of their network to spammers, often making $5000 or more per day in the process.

Botnets in recent years have grown considerably in size. The Conficker botnet for instance was said to have control of up to 10 million infected machines.

Malicious software is usually used to recruit new PCs into the botnet. This may include exploiting browser or operating system vulnerabilities, or by embedding viruses into legit software that users install on their systems.

a. Email client

Spam is not a matter of the email client. Its still reasonable to choose a client that fits your purpose. Some weeks ago we found out that most of the our authors are using different email clients, while none was using outlook (express). My advice would be to choose a email client other than outlook, there are lots of free ones available, for example.

Popcorn - (freeware supports one account profile)
Mozilla Thunderbird
Phoenix Mail
i.Scribe

b. Spam prevention

There are lots of ways to get rid of most of the spam and even prevent that your email addresses are collected by the spammers.

1. Don´t publish your email address on the net, if you have to publish it use a form that most spam collectors don’t recognize, for example instead of writing admin@deny.de write admin (at) deny.de without making it a link. you could also use a form mailer which hides your email address.
2. If you subscribe to certain services don’t use your real email address that your friends write to, basically you have two choices. Create a email address simply for the purpose to subscribe to certain services on the net. You could use free email services like

Gmx
Yahoo

or others, choose as you like.

If you want to subscribe to a service where you recieve a “confirm your registration” email but never recieve a email again from this service you could also use the following service.

Grensloth
Jetable
Mailinator
Spam.la
Spamspot

there is a big list of additional services available here.

When the service you want to subscribe to asks for a valid email address enter anything you like in the form (for mailinator.com in this case, check the website for instructions)

“youchoosethistext”@mailinator.com

Then switch to the mailinator website and enter “youchoosethistext” in the form field at the front page. You then see all mails that the user “youchoosethistext” recieved for the last hours. The mail from your service should be there and you can simply read and reply to finish your registration. The advantage is of course that the email address you instantly created will be gone after a few hours, leaving no traces of your real email addy or your identity. (just for the record, the mailinator guys of course have your ip address)

BUT, you should be aware that everyone is able to check the email for user “youchoosethistext”. So, if you registered at a forum like deny and people can see your email address (“youchoosethistext”@mailinator.com) they simply can order the forum to send out your password again to your email address and check at mailinator.com for that address and receive your password. That means, make sure that no one is able to see your email adress at the site.

3.Lets assume you already receive lots of spam but you cant change your email addresses. You could choose to use a program that blocks the spam before it is received in your email client. A program that basically sits between your client and the server of your email provider and checks all incoming mail whether its spam or not.

The best program for this purpose is in my opinion

Spamahilator

I did a test of some spamblocking programs and came to the conclusion that spamahilator is simply the best, its fast, it blocks about 99% of all spam without configuration.

Some of its functions are

- block certain words, you can edit, add, delete words
- block certain domains, allow domains to send
- block attachments of a certain type
- learn while receiving
- added functionality with plugins

Its really easy to configure and to maintain.

Other programs worth mentioning.

MailWasher – Shareware
G-Lock SpamCombat – Freeware

4. Email checkers

Problem with many new, modern worms is obvious: they gotta be downloaded by the mail client. Some of them (attachments) don’t even need to be run to start a nasty job thx of using OE exploits, so the message download an be dangerous.

Email checkers work in another way, they send a command only to get a number of stored new messages, some of them additionally retrieve subject lines of such messages, so it doesn’t harm in any way user’s computer.

CheckP3
GetMail

Thats all you need to know and do to prevent most of the spam on the net, fairly easy isn’t it ?

5. Filtering mail from spammers

Some anti spam programs are able to filter incoming mail that is send by mail addresses that are known to send spam. Internet Databases collect those addresses and provide lists containing them. Some programs allow to import this lists so you don’t have to add all ips manually.

Beware though, that adding a list might also filter out mail that you want to receive, if you want to add a list make sure to check it first before adding it.

Great listing of databases:

http://www.declude.com/Articles.asp?ID=97

Additional Information can be obtained:

Combat Spam
Spamfaq