Visual Studio 2010 hangs up when opening a .sql file

I launch VS 2010, and simply open any ordinary (or blank) .sql file and it shows up incorrectly drawn inside the IDE. It draws the document tab, but nothing else. If I type on the keyboard, VS locks up. This only appears to be a problem with files that have the extension ".sql" and has no bearing on the actual content. I also noticed that in the Solution Explorer, those .sql files show the icon that is the same one associated with .js files.

Problem solved. I was able to resolve the problem by running the DACProjectSystemSetup_enu.msi installer found on the VS2010-SP1 ISO under the root directory. You might also need to re-install DACFramework_enu.msi and TSqlLanguageService_enu.msi.

I believe the problem was created as a result of installing SQL Server 2008 R2 after installing VS2010.

I was able to fix the issue by:

1. Downloading the SP1 DVD ISO from here.

2. Executing DACProjectSystemSetup_enu.msi from the root of the ISO.

These 2 simple steps resolved it.