After update Xamarin I keep getting the pop-up message when try to build:
The Xamarin license file invalid and could not be recovered. Use Visual Studio Enterprise.
How to get rid of this annoying message?
From that item, it sounds like one possible workaround for Visual Studio 2015 might be to reinstall the previous Visual Studio 2015 Tools for Xamarin version (from the link in the yellow banner on https://store.xamarin.com/account/my/subscription/downloads), log out of the Xamarin account, and then upgrade back to the latest version.
There's a chance the quicker workaround idea I just added to the Developer Community item might also work, so you could give that a try first and delete the following files and directories:
EDIT: For the local scenario where I saw this myself, the correct file to delete was actually:
Xamarin Inc., as a wholly-owned Microsoft subsidiary acting as a separate legal entity, adheres to the Microsoft Privacy Statement: Privacy & cookies