I ran into this tale of woe, in which a trained tech. did an experiment and tried downloading software from a torrent. If you are not familiar with torrents they are best described as a system wherein everyone shares a folder on their system to make downloading easier. The usual warnings apply in that the downloads are usually illegal since they violate copyrighted law.
However, not to get involved in the legal aspects, there is another lesson to be learned. In the article it states:
I scanned my download with the latest version of AVG; all clear. I installed it and immediately all sorts of warnings informed me that my homepage was being changed; applications were trying to access the internet and several processes were attempting to place themselves in the start-up areas of Windows. Yikes!
Something in that torrent file was infecting my machine. After unplugging my network, (to avoid infecting the whole building), I noted filenames in the warning dialogues and frantically started searching. I found eight “droppers” and tried to delete them. No go; they were being used by Windows. After restarting in safe mode, I managed to delete a couple of them, but most had been integrated into Windows.
When Windows started, the viruses ran with it, and there was no way I could delete the infected files within Windows. I booted my machine using a bootable DVD, and, after mounting the drive, scanned it with several scanners, picking up 14 infected files.
I had to manually remove many other suspect files and edit the registry to remove viral hooks. Even then, after restarting Windows I still couldn’t find one particular process that almost had me tearing my hair out. Purely by luck I found the rogue process, which was disguised as a valid Windows system file. Interestingly, no virus scanner flagged it as a threat. Once removed, everything returned to normal.
So there you have it. In the final statement this summoned it up best:
What a way to spend an afternoon – if I had to pay for the clean-up, it would have been hundreds of dollars; all for a $40 piece of software.
I hope you get the moral of this story. I did.