When trying to promote a windows server 2016 TP5 ADC on a Windows server 2012 R2 DC then gets the following error.

Question

_{Monday, September 12, 2016 12:58 PM}



Verification of prerequisites for Active Directory preparation failed. Unable to verify whether schema master has completed a replication cycle after last reboot.
Exception: Unavailable Critical Extension. Server extended error: 8366. Server extended message: 000020AE: SvcErr: DSID-03210384, problem 5010 (UNAVAIL_EXTENSION), data 8610
.
Adprep failed to verify whether schema master has completed a replication cycle after last reboot.
[Status/Consequence]
The schema is not upgraded.
[User Action]
Check the log file ADPrep.log in the C:\Windows\debug\adprep\logs\20140723131051-test directory for possible cause of failure.

NOTE:

Even Adprep /forestprep which i run manually on win server 2012 R2 DC is giving the same error.

All replies (2)

_{Tuesday, September 13, 2016 8:58 AM ✅Answered}

Hi,

Try to use Active Directory Replication Status Tool to analyze the replication status for domain controllers in an Active Directory domain or forest. Download link:
https://www.microsoft.com/en-us/download/details.aspx?id=30005

Besides, as the message mentioned, check the log file ADPrep.log in the C:\Windows\debug\adprep\logs\20140723131051-test.

For common failures and possible solutions, you may reference blog - Troubleshooting ADPREP Errors:
https://blogs.technet.microsoft.com/askds/2008/12/15/troubleshooting-adprep-errors/

Best Regards,
Eve Wang

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_{Monday, September 19, 2016 3:05 PM}

Hi,

I am checking to see how things are going there on this issue. Please let us know if you would like further assistance.

You can click “Mark as answer” if the reply is helpful. It would make this reply to the top and easier to be found for other people who has the similar problem.

Best Regards,
Eve Wang

Please remember to mark the replies as answers if they help and unmark them if they provide no help.
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