After applied Exchange 2010 SP3 and Rollup 2 for Exchange 2010 SP3 on Mailbox Server Role server only, Exchange management shell (EMS) cannot start with the following error:

Mbx1.internal.contoso.com 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.

This can happen by many different causes. But in general this issue can be cause by the following code:

<codeBase version=”14.0.0.0″ href=”file:///%ExchangeInstallDir%bin\fil-PH\microsoft.exchange.core.strings.resources.dll”/>

These lines reside in:

C:\Program Files\Microsoft\Exchange Server\V14\ClientAccess\PowerShell\web.config.

There could be no %ExchangeInstallDir% environment variable specified in the server.

Resolution

In web.config file find and replace %ExchangeInstallDir% with C:\Program Files\Microsoft\Exchange Server\V14\ and save it, or copy the file from another Exchange 2010 Mailbox server to the problem server.

We could even create an environment variable in CMD (Command Prompt), with administrative privileges, using the following code (with SETX command):

setx ExchangeInstallDir "C:\Program Files\Microsoft\Exchange Server\V14\" /M