AVG Anti-Spyware did remove wintest.exe for me also
(And found even more spyware, although I sweep my computer almost weekly with many other programs like Ad-aware, Spy-Bot,Spy Sweeper, Hitman Pro 2,...)

AVG Anti-Spyware can be downloaded here:
http://free.grisoft.com/doc/20/lng/us/tpl/v5

I thank all the people behind this thread en this forum for their help.