I have a problem I can't find a solition for. After being on line for a while when trying to access a website I'll get a pop up that says

A pop up? Can you describe?

What exactly does it say? Could not be found? Anything else? Error? What exactly.

You might want to follow owen's Instructions and then post your log in the Spyware, Adware, Viruses and HijackThis Logs section (Not Here).