When you attempt to add clients to one of your “Business Critical” groups in SCOM 2007 you may get the error “The group can not be modified because there is no group population rule defined for this group”.

What does this mean?

Well, it means that you haven’t loaded the Business Critical Monitors themselves. When you added the Windows XP, Vista or Windows 7 Management Packs from the console it may not have added the XML files required for Business Critical Monitoring.

So how can you fix this?

Download the “Windows Client OS Operations Manager 2007 MP” MSI file and install it. This will extract a bunch of files to your hard disk. Amongst these files will be 3 new files, XML files that are the business critical ones you need.

In the SCOM Operators Console, import these 3 files. “Go to Administration, choose Import. Click Add from Disk and find those XML Files and import them”.

Now try and double click the Business Critical Groups in the “Authoring” view. The error is gone and they will now allow you to add client machines to the Explicit Members Tab.

Add the names of the computers you wish to monitor to this tab and you’re golden.