Problems like this can often be traced back to bad or corrupted Add-ons, like BHOs, (Browser Helper Objects), ActiveX and 3rd party toolbars like Google, Yahoo, etc.
IE7 has a safe mode option where it can be opened without any add-ons installed. Either right click your IE7 icon on the Desktop and select the 'No add-on' option, or if that option is not there, goto Start > All programs > Accessories > System Tools, then Internet Explorer (No add-ons).
IE7 will open without add-ons. You can surf the internet like that but since many web sites nowadays use add-ons to enhance the browsing, some web page may not behave as they should.
But that doesn't matter because the test is to see if IE7 works without Add-ons. If it does, then your next task is to find the offending add-on and eliminate it, (IE > Tools > Manage Add-ons).
Alternatively, you can take the brute force method and return IE to its default state. This will remove all add-ons, but will also remove all Favorites, all history, cookies, and any web site login and passwords that you have saved into IE. To do that, in IE goto Tools > Internet Options, then the Advanced tab, and click the Reset button.
You can backup your favorites beforehand, and restore them afterwards.
Mark
I'm having a problem with internet explorer 7. Every time I tried to open it I get an error saying explorer encounted an error and must close. I tried a system restore and that didn't seem to help. Any ideas on to fix it?

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