Enable F# interactive window in VS 2010?

How do I enable the F# interactive window in VS 2010 SP1, installed on Windows XP?

Alt+Ctrl+F doesn't do anything and neither do I see F# Interactive Window in the Other Windows开发者_如何学C menu.

I can however launch fsi.exe from a separate command prompt.

Any ideas what could be wrong?

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If you have not chosen the 'F# profile' for VS, then you might have to create a new F# project before this will appear on the menu, I forget?

(As per comments below, something was screwy in the install, but devenv /setup fixed it.)