Fix for SCOM 2007 Health Script failures

I had a problem with a couple of Windows Server 2003 domain controllers that were constantly showing as unhealthy in SCOM. The Health Explorer showed that the AD Op Master Roles monitor was failing. The Operations Manager event log would show the following events:

Event Type: Warning
Event Source: Health Service Script
Event Category: None
Event ID: 1
Date: 1/10/2008
Time: 5:50:05 AM
User: N/A
Computer: SADC01
Description:
AD Op Master Response : The script 'AD Op Master Response' failed to create object 'McActiveDir.ActiveDirectory'. This is an unexpected error.
The error returned was: 'The specified module could not be found.' (0x8007007E)

and

Event Type: Warning
Event Source: Health Service Script
Event Category: None
Event ID: 1000
Date: 1/10/2008
Time: 5:55:05 AM
User: N/A
Computer: SADC01
Description:
AD Lost And Found Object Count : The script 'AD Lost And Found Object Count' failed to create object 'McActiveDir.ActiveDirectory'. This is an unexpected error.
The error returned was 'The specified module could not be found.' (0x8007007E)

The solution is to run the OomADs.msi file in the C:\Program Files\System Center Operations Manager 2007\HelperObjects folder on the server having the problem. In my case, the domain controllers. Installation is quick and will not require a reboot. Once that's done restart the OpsMgr Health Service and you're good to go.