"Schema update failed: duplicate OID." Error running adprep

I am trying to upgrade a Win2000 native. I ran the adprep /forestprep
command on the dc that has all the fsmo roles including schema master. I
am a member of domain admins, enterprise admins, and schema admins. I get
the error message shown in the subject line. I have the following entries
at the end of the ldif.log file:
75: CN=NTDS-Site-Settings,CN=Schema,CN=Configuration,DC=WILMC,DC=co m
Entry DN: CN=NTDS-Site-Settings,CN=Schema,CN=Configuration,DC=WILMC,DC=co m
Entry modified successfully.
76: CN=Top,CN=Schema,CN=Configuration,DC=WILMC,DC=com
Entry DN: CN=Top,CN=Schema,CN=Configuration,DC=WILMC,DC=com
Entry modified successfully.
77: CN=ms-WMI-Som,CN=Schema,CN=Configuration,DC=WILMC,DC=com
Entry DN: CN=ms-WMI-Som,CN=Schema,CN=Configuration,DC=WILMC,DC=com
Entry modified successfully.
78: CN=ms-WMI-PolicyTemplate,CN=Schema,CN=Configuration,DC=WILMC ,DC=com
Entry DN:
CN=ms-WMI-PolicyTemplate,CN=Schema,CN=Configuration,DC=WILMC ,DC=com
Add error on line 1145: Unwilling To Perform
The server side error is "Schema update failed: duplicate OID."
77 entries modified successfully.
An error has occurred in the program

How do I fix this?

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