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After enabling my AD role in my Windows Server 2012 R2 and promoting it as a Domain Controller, I am no longer able to login locally onto the Windows Server itself.

Specifying my computername\Administrator or .\Administrator doesn't work.

Is it normal?

marked as duplicate by Greg Askew, Community Oct 11 '15 at 17:18

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up vote 5 down vote accepted

When you promote a server to a DC, it no longer uses the local account database. This database is only used when you boot your server in Directory Services Recovery Mode (DSRM), which makes the service inoperative as a DC while booted into this mode. This is the password you get to set when running dcpromo.

This is why your local account will not work - there is no local account any more.

Some more good info may be found in this forum thread on Technet.

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