"There is no editor available for 'C:\Documents and Settings\Steven\Local Settings\Application Data\Temporary Projects\WindowsApplication1\Form1.vb'
Make sure the applicaion for the file type (.vb) is installed"

This error can occur after you have been successfully using VB, and go to open a form in the Forms Designer. There may be many things causing this error, however the fix that worked for me was to reset the settings.

Open up a command prompt, and navigate to the \Program Files\Microsoft Visual Studio 8.0\Common7\IDE\ folder (replace 8.0 with your version).

Enter the command 'devenv.exe /resetsettings' (without the quotes). Hit enter, and Visual Studio will open. You should be able to successfully open the programs that previously displayed this error.

If this does not work, you can try to repair the installation by going to Control Panel, choose Add/Remove Programs, find Visual Studio and select repair.