MVC5 Null Reference with facebook login

Question

Im getting an null reference exception sometimes when I login with facebook using the out of the box ASP.NET mvc5 accounts controller.

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Answer 1

Clearing the Session as per the reply from Lee (marked as the answer) resolved this issue for us too. We have a pretty stock standard ASP.NET MVC 4 web app with Google and Facebook login also enabled running on Azure Websites and this was driving us nuts.

It would stop working every 12 - 24 hours or somewhere around that time period and restarting the website would make it work for the next period until it happened again.

I do however wonder why clearing the session works... it smells a bit like a framework bug (or perhaps an Azure bug in our case) unless I'm missing something.