This is a know issue, covered on MacFixit:
Many fixes suggested, removing certain plug-ins helped for me.
Try this (I found it on another list and it seemed to work for me...Rock Solid after several days
Try:
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* Quit Entourage
* Throw out all of the items you have in System Folder:Extensions:ActiveX
Controls
* Throw out System folder
references
PC Registration Database
* Empty the trash
* Restart Entourage�� � ��
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The fix is to take out the Windows Media Plug-In form the Internet Explorer Plug-Ins folder located in the main Internet Explorer Folder.
reinstall of Office 2001 CD
run the First Run from the CD
run IE first
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Todd Young found: "When I replaced IE 5 with the version provided on the Office 2001 CD-ROM, it worked like a champ." Others have also reported success with this.
* Quit Entourage, trash all the items in System Folder:Extensions:ActiveX Controls, trash the PPC Registration Database in the System Preferences folder, empty the trash, and restart Entourage.
* Christopher Erickson claims that deleting the Windows Media Plugin and DRM Plugin files, installed by Windows Media Player, will eliminate these crashes.
* A posting on MacInTouch cites a work-around suggested by Microsoft: Remove the following files from the Explorer Plugins folder: QuickTime Plugin, QuickTimePlugin.class, and Windows Media Plugin. Microsoft is supposedly working on an update that will fix this.
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A better work-around? A work-around for the Explorer/Entourage crash problem has been to remove the Windows Media Plugin (and possibly certain other) files from the Explorer Plugins folder. However, this obviously prevents the use of the features these plug-ins provide. David Rosenfeld may have found a way to resolve this dilemma. He moved the files to a new folder he created called �Plug-ins (disabled)," residing in the Explorer folder. This appeared to allow the plug-ins to continue to function in Explorer but not to trigger the Entourage-related crash.
Dylan Drazen found that while, removing the Windows Media Plugin file from the Plug-ins folder indeed eliminates the crashes, putting into a new "disabled" folder did not retain the functionality of the Plug-in (contrary to what David reported above).
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