Vista - Explorer.exe's high CPU usage?

[AgaBoogaBoo]

Explorer.exe has been using about 50% of my processing power, with processor 1 around 100% and processor 2 around 10-20%. I'm assuming that other applications are using the second core.

Any thoughts on this? I did a quick Google search to find others having the same issue, but didn't

 

[Aberforth]

This is a sign of a spyware, must be some dodgy program running in the background. First make sure there aren't any weird entries in the start up (msconfig>startup) and use ShellExView to disable all unwanted shell extensions and then run a Anti-Spyware Scan.

Edit: also check HOSTS file.