Hello @Jon Dehen ,
Thank you so much for your time and support.
I did the test in my lab. I configured a GPO with security Filtering. Deleted the Authenticated User group and added my security group with computer accounts. At first, it is domain local group and the GPO is applied without any problems. Then I changed the group scope to universal and the GPO is still applied without any problems. Then continue to change the group scope to Global and the GPO could also be applied successfully. So from my test, there is no need to restart the machines to take effect after changing the group scope.
Besides, I also tried to restart the machine, and the GPO is still be applied without any problems. So it is hard to say what changes caused this issue. As mentioned before, since the GPO is not applied now, we could enable GPSVC debug logging to further troubleshoot. We could run the following command to refresh the group policy and reproduce the issue:
gpupdate /force
Hope the information is helpful. For any question, please feel free to contact us.
Best regards,
Hannah Xiong
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