You could try ShellExView to see if there are any faulty entries:
http://www.nirsoft.net/utils/shexview.html
You can also post the Event Viewer errors. There is a copy/paste icon when you open the details of an error.
You can also try HijackThis as this issue is symptomatic of some infections.
HijackThis
--------------------------------------------------
Please read
THIS and after completing the steps outlined post a
HijackThis log over in that section along with a brief description of your problem.
Do not post HijackThis logs in this section please.
..................................
The security / spyware section of D-A-L works a little differently to the rest of the site. We currently only allow Head Security staff to reply to others threads to ensure a high level of support and quality is maintained with the daily issues which require a certain level of knowledge in this area.