Internet Explorer opening multiple windows unexpectedly

Found this post on the internet to fix this problem after you try out IE7 Beta with IE6 SP1 or higher installed. If you have this problem, it's extremely frustrating, I know, and that's why I decided to post this solution. Just delete the registry key mentioned and you're good to go. Spyware/Virus/Browser Hijack scanners don't work to fix this. I wish I had the original link I found this on to give credit to the poster, but I don't, I just saved the text in a note. Sorry guys.

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IE December Security Update – addressing scattered reports of odd browser behavior

We have received scattered reports of users experiencing odd browser behavior after installing our most recent security update. Some of you have reported opening a browser window that promptly hangs IE, others have reported opening links that render blank, and finally we have reports of multiple windows opening when initiating a browser session. After investigating several of these reports, we have traced these issues to a common source.

If a user has ever attempted to run IE7 Beta1 in an unsupported side-by-side configuration with a version of IE6, IE7 Beta1 puts a registry key on the machine the first time a user executes the IE7 version of IEXPLORE.EXE. This key is part of an normal IE7 installation on XP, and will not be configured correctly if an unsupported side-by-side install is used. When IE7 is installed using the installer, the key should be removed properly upon uninstall. A machine can also load this registry key and not remove it during a failed IE7 installation.

To address this issue on a machine running IE 6 SP1 with our most recent security update, locate and delete this entire key from the registry of the affected machine: HKEY_CLASSES_ROOT\CLSID\{c90250f3-4d7d-4991-9b69-a5c5bc1c2ae6}. If you are running IE7 Beta1 in a side-by-side scenario with another version of IE, this is not a supported scenario. Please uninstall and reinstall IE7 Beta1 in the recommended manner.

Thank you all for your blog comments reporting this incident. Your valuable feedback allowed us to locate this issue in IE7 Beta1 and investigate how to prevent the problem in future.

- Jeremy Dallman

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