Ispconfig3 unable to store client on DNS and email domain records

After upgrading from Ispconfig 3.0 to 3.1 odd things started to happen. For example, when saving a DNS secondary zone it would not store the client selected. Same thing when saving an email domian, client info and spam filter setting just would save.

The solution turned out to be simple. Gentlemen – clear your cookies and login again! Problem solved.