“AuthorizationManager check failed.” On Exchange 2010

After uninstalling Exchange 2010 Hub Transport Server on one of my Servers. I received the following errors:

Restoring services
Failed

Error:
The following error was generated when “$error.Clear(); if (Test-Path $RoleBinPath\ServiceControl.ps1) { & $RoleBinPath\ServiceControl.ps1 EnableServices $RoleRoles.Replace(‘Role’,”).Split(‘,’); & $RoleBinPath\ServiceControl.ps1 Start Critical }” was run: “AuthorizationManager check failed.”.

AuthorizationManager check failed.

Error:
The following error was generated when “$error.Clear(); if (Test-Path $RoleBinPath\ServiceControl.ps1) { & $RoleBinPath\ServiceControl.ps1 EnableServices $RoleRoles.Replace(‘Role’,”).Split(‘,’); & $RoleBinPath\ServiceControl.ps1 Start Critical }” was run: “AuthorizationManager check failed.”.

AuthorizationManager check failed.

Rebooted the machine. Upon start up I found all the Exchange services were failed to start. For obvious reasons, launching EMC and EMS also presented similar errors.
After googling around (which I found many people experiencing the same problems when attempting to install Exchange 2010 SP1). I ran across this article:
http://support.microsoft.com/kb/981474

After reading the Causes Section. I ran the Get-ExecutionPolicy, which also failed complaining about COMObjects. I went into the Services.msc console and found that NOT ONLY Windows Management Instrument (WMI) service was disabled, the W3PSVC (World Wide Web Publishing Service) was also disabled.

SOLUTION:
1. Re-enabled WMI service and start it. (This fixed the AuthorizationManager issue)
2. Re-enabled W3PSVC service and start it (This enables EMS – Exchange Management Shell to work)

PERMANENT SOLUTION:
The reason that causes this was because we had set our ExecutionPolicy to RemotelySigned via the Powershell prompt locally. Apparently, Microsoft expected people to enable this via Group Policy. Please go back and read the article posted above.

Creat a Group Policy and apply it to the Exchange OU that does the following:

Set WMI service to automatically start.