When Anki doesn't start on Windows (debugging steps)

Please ensure you're on the latest Anki 2.1 version. Instead of running Anki directly, please use Start>Run and type cmd.exe. When a console window appears, please type

cd \program files\anki
anki-console

Presumably Anki will fail to open like before. But it should give you some lines of debugging info; please copy&paste or screenshot the text and attach it to your support ticket.