KB ID 0001252
I tried to get access to OWA on my Exchange 2016 server, and was greeted with this;
Something Went Wrong
We’re having trouble getting to your mailbox right now.Please refresh the page or try again later
I’ve pointed it out on the image above, but it’s easy to miss, look at the time stamp on the error, and compare it to the correct time. The two are not the same.
This is a known problem on both Exchange 2013, and Exchange 2016. It’s fixed in one of the cumulative updates, I was still on the RTM install version, so I updated it.
After that it worked fine.