Recently I had a customer go through a routine upgrade from Exchange 2010 SP2 RTM to Exchange 2010 SP3 that I performed, and after the patching was done everything was fine until we realized management on the Exchange UM servers wasn't working. We were not even able to remote manage them to configure new users for UM features, so we had a very real problem here which is why I was called in.
Symptoms
The most evident errors seen were in the management interfaces themselves.
In the powershell console the major error was: WinRM client cannot process this request. It cannot determine the content type of the HTTP response from the destination computer.
I now began troubleshooting deeper, starting with an easy pass through the event logs to find an ASP.net error which then led me to the discovery in the second screenshot. I found the Power Shell "Server Error" in two ways, from IIS manager I selected the
Resolution
Now like many of you, I went to Technet, google and my own archives of case notes looking for answers and found many articles that gave me hope but there it was very scattered.
Fix 1
This one below I thought for sure was the source of all my problems.
Resolving WinRM errors and Exchange 2010 Management tools start-up failures
http://blogs.technet.com/b/exchange/archive/2010/12/07/3411644.aspx
Unfortunately, while this blog article has many great suggestions and a neat tool that actually did find an issue and fixed a problem, it did not fix my specific issues with WinRM connectivity. I still continued to have Remote Management problems with my Exchange 2010 SP3 even though it continued to function properly as a UM server.
Fix 2
How to Repair or Reinstall .NET Framework 3.5/2.0
Next
This did resolve the ASP.net errors and the SERVER Errors when browsing
So we press on! Never Retreat, Never Surrender!
Fix 3 (The one that works)
I am not totally sure how I found this, call it luck, Wizardry, Magic, extreme fatigue whatever but I'd read enough articles that night to give me enough evidence to believe a posting that made a rather outlandish claim about our beloved Exchange.
On the Exchange server having the issue, open the web.config file for the
Exchange 2010
D:Program FilesMicrosoftExchange ServerV14ClientAccessPowerShell
Exchange 2013
D:Program FilesMicrosoftExchange ServerV15ClientAccessPowerShell
Once you open the web.config perform a search for any references
Yes
Now perform an IISreset and test, this resolved the issues for me and all is working flawlessly now. I hope this Blog post helps you and saves you a bit of time.