So I have been having this issue with Visual Studio 2008 for the past couple of days which has caused me quite a lot of frustration. I would be in the IDE and when I went to edit the source of an ASPX page the IDE would appear to freeze and not take focus as if there was a dialog sitting behind the window that I could not access. Clicking anywhere on the window would just cause the error sound in windows.

The only way I could continue working was to kill Visual Studio in task manager. I tried rebooting my machine but the problem still persisted. I decided to turn to Google to try to resolve my issue.

The culprit… Office 2010! It seems that uninstalling Office 2007 when upgrading to Office 2010 x64 had broken the web authoring component of Visual Studio, according to the KB article from Microsoft; this was due to a bad uninstall of a MSXML5 component.

The solution: From the KB Article (KB2022915)

You can work around this problem using these steps:

1.  If an automatic upgrade was performed from Office 2007 (32-bit) to Office 2010 (32-bit) on a 64-bit OS:

• In Add/Remove Programs, locate "Microsoft Visual Studio Web Authoring Component"
• Right-click and select "Change"
• When a dialog opens, choose "Repair" option

2.  If you manually uninstalled Office 2007 on a 64-bit OS:

• In Add/Remove Programs, uninstall "Microsoft Visual Studio Web Authoring Component"
• If you are using Visual Studio 2008:
  • From the Visual Studio 2008 media, navigate into the WCUWebDesignerCore folder and install WebDesignerCore.exe
  • If you were upgraded to Visual Studio 2008 SP1, you must reinstall Service Pack 1 for Visual Studio 2008.
• If you are using Visual Web Developer Express:
  • Uninstall and reinstall Visual Web Developer 2008 Express

So now my Visual Studio appears to be working correctly again! Woo hoo, now back to work!