Visual Studio has lost project templates

I'm trying to add a new project to my solution, but Visual Studio has forgotten where the project templates are. In the screenshot below, there should be some stuff in the templates list:



I've checked that the templates actually exist in their usual location:

C:\Program Files\Microsoft Visual Studio 8\Common7\IDE\ProjectTemplates\CSharp

and had a good old rummage around Google, but to no avail. Does anyone know anything about this?

Update: Having read this MSDN page, I tried running devenv /setup, and they're all back again.