I have seen multiple threads and postings on the ECP failing with HTTP error 500 - but (like many others) I have not run across one that seems to exactly fit my situation ...
I have a 4 node DAG (Exchange 2013) which has been running since late last year. We had a datacenter failure yesterday and lost two of our DAG nodes and two additional servers in the Organization (not DAG members).
While I don't think the following is relevant I want to provide as much information as possible. Previously the File Share Witness was in the datacenter that did NOT fail ... but was moved to a third datacenter - which did not fail during this outage.
During the outage the ECP would NOT load. When provided with wrong credentials I would receive the 'incorrect username or password' message. Correct credentials would receive an HTTP error 500 - 'website is down for maintenance or has a programming error' (like we didn't know that second part - haHAha j/k).
The Exchange system was fully accessible via PowerShell but the ECP would not display until the other datacenter (and the associated servers) came back online.
So - I'm assuming I have something misconfigured somewhere ... but I don't know where to start. I spent most of the day yesterday trying to figure this out and got nowhere.
It seems as if my ECP is tied to a specific server - one of the servers that was offline yesterday. How would something like that happen??
Thanks in advance for any thoughts/guidance ...
