Hotoffers infections have been a pretty popular topic here in the last few months. Please review the suggestions given in our recent hotoffers-related threads and see if one of those solutions works for you:
http://www.daniweb.com/techtalkforums/search.php?searchid=373139
If you cannot find a fix that works, or if you have any questions about the procedures described in those threads, please repost here. When you do, it would be a good idea to give us a HijackThis log as well:
Download HijackThis onto your jump drive:
http://www.stevewolfonline.com/Downloads/DMR/Spyware%20Tools/HJT/HijackThis.exe
You should be able to run HJT right from the jump drive, but if not, create a folder on the hard drive for HJT and move it there. A folder such such as C:\HijackThis or C:\Spyware Tools\HijackThis will do.
Run HijackThis, but do not have HJT fix anything yet; only have it scan your system! Once the scan is complete, the "Scan" button will turn into an option to "Save log...". Save the log in the folder you created for HiajckThis, open the log in Windows Notepad, and cut-n-paste the entire contents of the log here. The log contents will tell us a lot about what "nasties" have crept into your system, and once we analyse the log we can tell you what to do from there.