This is the most obscure bug I’ve solved in recent times. It showed up a few days ago in my work place where we have to use Office 2003 and some 2007 modules. I assume it’s been triggered by some recent update but it’s an old problem.
If you try to edit in Sharepoint 2007’s  “Datasheet” view using Internet Explorer 7. IE 7 crashes instantly. You may see a similar problem with editing Office documents in SP 2007.
The crash details mention MOSS.DLL, but various net resources point to a conflict between two Office 11 and Office 12 DLLs: OWSSUPP.DLL and MOSS.DLL. In particular IE 7’s add-on manager causes it to load the wrong copy.
Yes, DLL Hell again.
Useful references include:
- Groove Advisor The Groove Blog Microsoft Office Groove 2007 with Office 2003
- Office XP integration problem
- SharePoint - IE Crashes when opening Office documents (most complete discussion)
I followed the advice to rename OWSSUPP.CLL in the Office 12 directory. That fixed my problem and Project still loads.
After I did that I found this post: SharePoint - IE Crashes when opening Office documents recommending a repair using Microsoft Diagnostics. That post refers to the Office 2007 SP1 Hotfix package, but that’s hotfix is too old to use now.
I would suggest trying the Diagnostics repair first. If that works please add a comment to this blog post. If it doesn’t work, then rename the Office 2007 DLL as above.
I will update this post as a I learn more.
 Microsoft calls Sharepoint “MOSS”. They sure know how to name things.