I get this message on windows 2008 r2 Exchange 2010 sp3

Cannot load file or assembly

Has anyone seen this?

If you are receiving the error 'cannot file or assembly' 4.0.0 then there is an error with the application version pool in on e of two places:

1. Under IIS Application pools the MSExchangePowerShellAppPool application pool containing the powershell application has had its ASP version set to 4.0 when it should be set to 2.0

2. The IIS application pool 'ASP.NET v4.0 MSExchangePowerShellAppPool' contains the application powershell when it should be under MSExchangePowerShellAppPool and so you must go to the 'ASP.NET v4.0 MSExchangePowerShellAppPool' application pool, click 'view applications' and select powershell and then select 'change application pool' and change the application pool back to being MSExchangePowerShellAppPool which is running under ASP version 2.0

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