An irritating error suddenly started on my exchange-servers last night.
When starting both EMC and Management Shell i started getting this on my HUB/CAS-server:
“[FQDN] Connecting to remote server failed with the following error message : The WinRM client cannot process the request. It cannot determine the content type of the HTTP response from the destination computer. The content type is absent or invalid. For more information, see the about_Remote_Troubleshooting Help topic.”
There are about a million things you can check here.
THIS is a good place to start, checking the WinRM, kerberos-modules in IIS, removing and readding the WinRM IIS-extension etc. I did everything I could find, three times.
What ultimately fixed it for me:
I had updated all servers and installed IE 9. Everyone who have done this on their management servers, knows they start being spammed with errors when closing EMC, saying you haven’t closed all dialog boxes. What I had done, was removing IE9 on the CAS/HUB to get rid of this annoyance. However, after rebooting the server a week later, EMC stopped working with this error.
Reinstalling IE9 and iisreset fixed everything. God knows why.