Here is the procedure I used from KB817433. Not sure why they say you can use Active Directory Users & Computers - I had to use Adsi Edit.
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You can enable inheritance on the adminSDHolder container by using ADSI Edit or Active Directory Users and Computers. The path of the adminSDHolder container is CN=AdminSDHolder,CN=System,DC=<MyDomain>,DC=<Com>
Note If you use Active Directory Users and Computers, make sure that Advanced Features is selected on the View menu.
To enable inheritance on the adminSDHolder container: 1. Right-click the container, and then click Properties.
2. Click the Security tab.
3. Click Advanced.
4. Click to select the Allow Inheritable permissions to propagate to this object and all child objects check box .
5. Click OK, and then click Close.
The next time the SDProp thread runs, the inheritance flag is set on all members of protected groups. This procedure may take up to 60 minutes. Allow sufficient time for this change to replicate from the primary domain controller (PDC).
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