Buggy, definitely. Worth the hassle, yes.
The following occurs when trying to compare two schemas using the Data->Schema Compare->New Schema Comparison menu option and selecting two existing connections. Clicking 'Edit Connection' when the connections are selected you can't edit them either (the dialog just disappears) and after a few attempts, VS goes bang! To work around this error, go to Server Explorer and delete any old connections (you may need to delete them all to get it working).
You might get this a few times;
You'll need to quit VS and start again once that error starts popping up then the dodgy connections should have gone. If they are still there, keep hacking through them trying to delete (ignoring the errors) and restart again. If you still can't get rid of the dodgy connection, try expanding the node for it in server explorer. I got the following error which gave me a GUID I could hunt through the registry for to delete the data provider. Turned out my issue was caused by the VistaDb uninstaller removing the required files for a connection (which is what I wanted) but Studio fell over when it saw the headless connection.
I found some references to the dodgy connection under; HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\9.0\DataSources\{GUID-OF-PROVIDER-HERE}. After deleting all the references in the registry to it and the .suo file for the solution I found it was held elsewhere. So on with the hunt.
So far, one hour spent on this and no joy. Searching the C drive for all .udcx files (seems these hold connections) yielded nothing either, but very slowly. Reset the development environment (/resetskippkgs and /resetsettings as command line options to msdev), nowt.
Finally I fired up SysInternals Process Monitor and waded through the torrent of data it vomited when VS starts up. I happened across the directory; C:\Users\Ryan\AppData\Roaming\Microsoft\VisualStudio\10.0\ServerExplorer In there is a file ending in .SEView, this is where this junk is held.
I copied the file to a backup in the same directory (mistake) and tried again after editing the file, but the duff connection reappeared! Looking in Process Monitor, VS loads ALL files in that directory ending in SEView, so I moved them out completely and all started up well. Success, I can now compare two databases, two hours later!
The time technology saves me!
