An orphaned GPO is the result of what happens when you remove a computer from a domain without removing its applied Group Policy Objects. In order to prevent this from happening, it is a good idea to first move the computer in Active Directory into an OU that has no GPO’s applied to it before removing it from the domain completely. It is also a good idea to make sure that this OU is blocking policy inheritance from OU’s above it. Doing this will completely ensure that you all group policy settings are removed from the computer in question.
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Chris Sanders is the network administrator for one of the largest public school systems in the state of Kentucky. Chris's specialties include general network administration, windows server 2003, wireless networking, and security. You can view Chris' personal website at www.chrissanders.org.