I am the holder of a Xamarin.Mac Business license. I have used it to activate my copy of Xamarin Studio on my iMac. However, I have suddenly found that Xamarin Studio will no longer embed the Mono runtime (even after a clean and rebuild), or run my custom post-build script that code-signs and sandboxes the application. (No license-violation errors are issued.) What’s more, when I go to Xamarin Studio / Account, my account is listed as having only the useless Xamarin.iOS Starter license — there is no sign of Xamarin.Mac! Logging out and in again does nothing. I have verified on the Xamarin website that my license is still active; it will not renew until July 2014. What is going on?