Keyset does not exist / Identity invalid

I ran the iisreset command and my problem was sovled

I found a couple of links that led me to a solution.

In c:\windows\system32\inetsrv\config\applicationHost.config I removed all the configProtectedData entries.

Then I removed everything in %ALLUSERSPROFILE%\Microsoft\Crypto\RSA\MachineKeys

I ran iissetup.exe /install SharedLibraries from the inetsrv directory, which resulted in a "Failed = 0x80070005"

I then was able to set up my application pools as if nothing happened.

See also https://techcommunity.microsoft.com/t5/IIS-Support-Blog/Keyset-does-not-exist-exception-from-HRESULT-0x8009000D-or-or/ba-p/342955 for a more detailed explanation

I tried to change the Identity of Application Pool on a remote server and it failed with the above error. I RDP into the remote machine and then tried to update the Identity using local IIS Manager and it worked.

I had the same error-message because my user was not member of the "Local Administrators" group.

I was able to connect to the server because I was member of the "Remote Desktop Users" group.

I was able to open IIS Management and to change settings, but when I clicked on the "OK" or "Save" button - I got the "Keyset does not exist" - error message.

So my advice - check if you are an administrator.