Go to http://www.trendmicro.com and download HijackThis. Install it and click to Scan and Save a Log. The redirect will show up in the first few entry lines - R0 and R1 - possibly F2 but only tick to remove something if you're sure about it. If you aren't, copy and paste that log back here for analysis.
HJT isn't always a complete fix - it's a guide to what needs fixing so the problem will not necessairly go away after using it.[/#000ff]