Can't join domain


I previously used an XP computer on the domain wth a name like 'mylaptop'.

I replaced the drive and have Windows 7 Ultimate installed and am unable to join the computer 'mylaptop' to the domain. I've done these things...

1. Ran NSLOOKUP to verify I can see the domain controller
2. Manually entered the DC IP number in DNS
3. Disable IPv6
4. Enabled netbios over TCP
5. Can successfully ping both DCs
6. Disabled all firewalls
7. Tweaked secpol.msc settings as described in other posts
8. Asked the domain administrator to manually remove the computer from the domain.

I'm not an admin, but I was given rights to join a computer to the domain. I can successfully use remoted desktop to get to other computers. I can browse the network and manually enter credentials to see shares. Networking seems to be OK.

When I attempt to join, I get the message:

Your computer could not be joined to the domain because the following error has occurred: No mapping between account names and security IDs was done.

or this error:

The join operation was not successful. The could be because an existing computer account having the name xxxx was previously created using a different set of credentials. Access is denied.

Any help is appreciated

I am guessing you can join a computer to the domain if the AD admin creates the computer in AD first. Get them to create the computer in the correct OU in Active Directory and try again.


Noob Whisperer
ottogre is correct that should get it done, but just to check and make sure that you still have the "Allow join computer to domain" rights you might want to experiment with a name change on the computer perhaps laptop2, or something else equally as subtle and see if that makes any difference.

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