Internet Explorer 7's No Add Ons mode
One of the lesser known features of Internet Explorer 7 is the "No Add Ons" mode.
A shortcut is automatically added to the All Programs Menu in the System Tools folder (All Programs, Accessories, System Tools) when Internet Explorer 7 is installed. Alternatively, you can create a shortcut on your desktop or QuickLaunch bar with the following target path:
"C:\Program Files\Internet Explorer\iexplore.exe" -extoff
Primarily a troubleshooting tool, No Add Ons mode allows you to start IE with all add-ons such as toolbars and activex controls disabled. If you are seeing problems when using IE in normal mode, and those problems go away when using No Add Ons mode, then obviously a third party product is at issue. Use the Manage Add-Ons tool to disable all Add-Ons, start IE in normal mode then re-enable the add-ons one at a time, testing as you go, to work out what which product is causing a problem.