Today I was preparing an exchange server 2013 CU update. So I made backups of all exchange server instances and then I installed the “January 2017 windows update package”. After rebooting all the exchange servers, I’ve got the HTTP 503 error. I was a little bit shocked because I didn’t anything except installing windows server updates. I also tried to open the “Exchange Management Shell”, but it also failed with the following message:
New-PSSession : [XCH01.domain.local] Connecting to remote server XCH01.domain.local failed with the following error message : [ClientAccessServer=XCH01,BackEndServer=XCH01.domain.local,RequestId=357032aa-2312-477e-be88-8d99 db9027c5,TimeStamp=12/02/2017 14:40:28] [FailureCategory=Cafe-SendFailure] For more information, see the about_Remote_Troubleshooting Help topic.
I’ve spent some time to troubleshooting and find out, that the exchange server Backendsites did loose the SSL certificate (WHY????).
So I was not able to figure out, why it happened. But it was very easy to fix.
- 1.) Open the “IIS-Manager”
- 2.) Navigate to “sites”
- 3.) Right click on “Exchange Back End”
- 4.) Select “Site Bindings”
- 5.) Choose “HTTPS Port 444” and click on “edit”.
- 6.) Select the right SSL certificate and confirm it with “Ok”
- 7.) run “cmd as admin”
- 8.) type in iisreset