On several systems at different sites I’ve noticed an abundance of the following errors in the Operations Manager 2007 logs:
Event Type: Warning
Event Source: Health Service Modules
Event Category: None
Event ID: 21405
Date: 2009-04-21
Time: 09:00:26
User: N/A
Computer: MASKED
Description:
The process started at 09:00:26 failed to create System.PropertyBagData, no errors detected in the output. The process exited with 0</pre>
Command executed: "C:WINNTsystem32cscript.exe" /nologo "NetworkAdapterCheck.vbs" MASKEDCOMPUTER.DOMAIN 7 false true false Working Directory: C:Program FilesSystem Center Operations Manager 2007Health Service StateMonitoring Host Temporary Files 150958
One or more workflows were affected by this.
Workflow name: Microsoft.Windows.Server.2000.NetworkAdapter.NetworkAdapterConnectionHealth
Instance name: 7
Instance ID: {A6F89C78-1217-578E-B03D-5ED377A9A40B}
Management group: MASKED
For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Always the “NetworkAdapterCheck.vbs”. Always “The process exited with 0″ which usually means that life is A-OK.
This may be a result of your AV-software blocking the scripts.
The first thing to do would be to exclude HealthService.exe and MonitoringHost.exe. If this doesn’t work, try excluding the entire C:Program FilesSystem Center Operations Manager 2007Health Service State directory.
There is a bug-report on Microsoft Connect that you can add your vote to if you cannot get rid of the problem. But ofcourse, if you have a solution, do post it here or on the bug-report. 
[...] Server 2000 Operating System Management Pack f
[...] Server 2000 Operating System Management Pack för Operations Manager 2007 that is causing the failed to create System.PropertyBadData error i wrote about earlier. This information in also available on [...]