It all begins at a website or server. This is the starting point and it might be a good idea to start validating that server before even thinking about downloading files from there. This can be done manually by performing some searches in search engines but also automatically with browser add-ons or plugins like Web of Trust, McAfee’s Site Advisor and a plethora of other respected programs including local security software that can also check websites and servers.

The second step involves downloading the file to the local computer system. There is not a lot that can be done here in this step. The only defense are security software programs that are installed on the computer system that should scan the file and report back to the user if they believe it to be malicious. Cautious users can also use one of the many online virus scanners to upload the file and scan it online. Services like Virus Total scan the files with more than a dozen different up to date antivirus engines resulting in a more precise analysis of the file.

Another option is to check the hash values of the downloaded files to make sure that they have not been tampered with. This only makes sense if the developer is displaying the values on a trusted website.

It is pretty safe to assume that the file is safe and can be executed on the computer system if it did pass the tests. There is however a last step that can be done to add the extra mile of security: Virtualization. Programs like Sandboxie or VMWare Player make it possible to execute programs in a closed environment for testing purposes. The benefit of this approach is that they cannot harm the rest of the computer system if they should be malicious.

Did we leave something out? Let us know in the comments.

To give an example. Should a user run Ad-Aware, Spybot Search And Destroy, Spyware Terminator or one of the other dozen or so anti-spyware applications that can be used freely for personal non-commercial use.

To much choice can be confusing and this article tries to narrow down the list to security applications that are recommended most of the time. Some users will disagree with the choices and they have every right to do so. You can rest assured on the other hand that the selection of tools should be sufficient to scan a computer system thoroughly

Anti-Spyware:

Spyware usually refers to malicious software that tries to spy on the user or serve advertisement to him. This can be done with tracking cookies, changing the user’s homepage or showing popups from time to time.

• Spybot Search And Destroy – Spybot Search and Destroy is updated regularly and does not confuse the user with different versions like Ad-Aware does with Ad-Aware Free, Plus and Pro.
• Spyware Terminator – A tool that has been downloaded more than 17 million times should do a good job. Spyware Terminator is fast and efficient.

Anti-Virus:

Anti-virus applications create probably the most controversy. There is so much choice of free and commercial applications that makes it nearly impossible to make a decision. The applications protect the computer in realtime and can scan the computer thoroughly.

• AVG Anti-Virus – A classic anti-virus software that provides protection against viruses, rootkits and spyware.
• Free AV – Antivir protects the computer against viruses, rootkits, dialers and phising.

Rootkits:

Rootkits have been gaining popularity in the last years and one could say that Sony did not have a small part in raising the public’s perception of rootkits with their music CDs that contained a rootkit in order to prevent customers from copying the music.

• Rootkit Unhooker – a portable rootkit scanner with a size of under 100 Kilobyte.
• Gmer – is another tool to scan the computer for rootkits.

Is the list missing any categories? Would you put other applications up there (I know you would so let me know)?