Wikipedia
WinFixer is a family of scareware rogue security programs developed by Winsoftware which claim to repair computer system problems on Microsoft Windows computers if a user purchases the full version of the software. The software is mainly installed without the user's consent. McAfee claims that "the primary function of the free version appears to be to alarm the user into paying for registration, at least partially based on false or erroneous detections." The program prompts the user to purchase a paid copy of the program.
The WinFixer web page (see the image) says it "is a useful utility to scan and fix any system, registry and hard drive errors. It ensures system stability and performance, frees wasted hard-drive space and recovers damaged Word, Excel, music and video files". However, these claims were never verified by any reputable source. In fact, most sources consider this program to actually reduce system stability and performance. The sites went defunct in December 2008 after actions taken by the Federal Trade Commission.