Have an installation of SQL Server 2012 Developer Edition on my development laptop (Windows 7) which has been installed for about 2 years, with several databases, and Reporting Services also installed - this installation is used daily, and was still able to connect using SSMS 2012 as recently as yesterday.
Today, after no changes to my development laptop, when I try to launch SSMS, I'm suddenly getting some unexpected error dialog boxes.
First error dialog states something like "VsDebugPresentationPackage, Version=10.0.0.0 didn't load correctly", then another error stating "Microsoft.SqlServer.Management.SqlStudio package did not load correctly", and then an error along the lines of "Failed to open connection dialog ..... Object reference not set to an instance of an object Microsoft.SqlServer.Management.SqlStudio".
I've established that I can still connect using SQLCMD, and also I can still various Reporting Services reports that run against databases on this installation of SQL Server 2012 so to all intents and purposes the actual databases and database engine are still working OK, it's just the SSMS connectivity that has stopped working, and I just can't see why.
I've tried reinstalling just the SSMS 2012 client tools, but that has not solved this error, so any suggestions on how to resolve this will be greatly appreciated (unfortunately, I haven't got my original SQL Server 2012 installation DVD onsite with me today).