The sleazes at Antivirus XP are at it again, and taking their nastiness to another level with FileFixer Pro. It is a very dangerous bit of spyware, because it keeps you from accessing your own data.
Like all the other version of Antivirus XP (2008, 2009, 360), File Fixer Pro appears as a popup while you're browsing the web that warns you in very heated terms that you files are corrupted and you'll need to install the program to fix it.
Don't do it!
Once the program is installed, it encrypts your files. They're perfectly good, but you need to buy the software (for $60 or more) in order to read them. If you do buy it, it will (probably) fix things -- but they now have your credit card and can run up charges on it.
While there are ways to remove File Fixer Pro, the files will remain encrypted. At the moment, there is no way to fix this. (Added 3/25: Tools are now available).
If a window pops up with this warning (or any other virus warning), close your web browser immediately. The software won't install without your help.
Be very careful when browsing the web. If you get a pop up warning you about a virus or problems with your computer, don't believe it.
Here is a discussion; information is still scarce, so be warned.