How I got Word, Excel and PowerPoint to start working again
At VSLive Orlando (Oct 4-7), I am giving a talk on the Office 2007 Open XML File Formats. In the talk, I will have lots of examples of how to use the Open XML SDK to programmatically manipulate Word, Excel and PowerPoint documents from VB/C# code without having to start Word, Excel or PowerPoint. It is a cool topic and a very nice tool to have in your app building arsenal.
Last Friday, I was putting the finishing touches on my demos, when PowerPoint crashed. No worries though. Word, Excel and PowerPoint docs are now stored as XML and when you use the SDK to modify the docs, you are modifying the XML. If you make a mistake in your code, the XML is invalid and the Office app can't read/open the document. So PowerPoint crashed after I opened a presentation I had modified. But then I opened a presentation I had not modified and it crashed. And it crashed when I opened PowerPoint without opening an existing presentation. And to make matters worse, Word and Excel also now stopped working as soon as I started them. Interestingly, Office, Access and OneNote worked fine. Was it a coincidence that the 3 apps that let you manipulate the XML in docs were the ones not working?
I did a repair. Word, Excel and PowerPoint continues to stop working immediately on starting them. I rebooted. Same. I stopped working since it was Friday and said I will fix this Monday. This morning I uninstalled Office and reinstalled. Same problem. I tried starting them in safe mode. Word would start in safe mode, but Excel and PowerPoint would not. I Binged and Googled for solutions. I tried registry modifications (see http://support.microsoft.com/kb/921541), but still had the same results.
Someone suggested I try natively debugging. I downloaded WinDBG and tried that, but I honestly could not figure out what I was looking at. I searched through the event log and saw all the crashes, but couldn't get any insight.
I did more Binging and Googling and saw that someone had an issue where Excel stopped working and explicitly blamed the Office Live Add-in. So I uninstalled the Office Live 1.4 Add-In from my computer and hallelujah!! Word, Excel and PowerPoint all now work. This add-in lets you save Word, Excel and PowerPoint docs to an Office Live Workspace. That explains why only those apps had the problem, not the others.
Why did the Office Live Add-In suddenly cause Word, Excel and PowerPoint to stop working? I don't know and I don't know how to know. All I know is that I spent about many many hours on this and finally am back where I was before all heck broke loose. And that means, I can get on with my normal work, including playing with Visual Studio 2010, which I will blog about soon.