Question : windows 2000 server - credentials confllct

Hello,
I hve 3 computers - one is running windows 2000 server- one is running windows 2000 pro and last one xp.
I have not networked in a long time - I have windows 2000 server pc as domain controller- i have active directory installed- each computer can ping and find other computers-
but when I try to join the 2 computers to the domain- it gives me password box and when I enter name and password - it says 'the following error occured the credentials conflict with existing set of .....'
can you point me to some things to look at that may be wrong- I want to get database on server one and practise sharing some stuff- I am hoping I don't have to go back and study for days long article to figure out problem
thank you

Answer : windows 2000 server - credentials confllct

This might be of help...

http://support.microsoft.com/kb/197987

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To resolve this problem, blank out the Username key in the registry for HKEY_CURRENT_USER\Network:
Log on as an administrator at any workstation.
Click Start, click Run, type regedt32, and then click OK.
Select HKEY_USERS, but do not open.
From the Registry menu, click Load Hive.
This will bring up a Load Hive dialog box. Locate the Ntuser.dat file for the user with the errors. Select the Ntuser.dat and click Open. You may enter any string for the Key Name. Use TEST for ease of use pertaining to the remainder of this article.
Locate the Username value under the following key in the registry:
HKEY_USERS\TEST\Network\Username
Delete the string for Username (leaving it blank is sufficient).
Select the TEST hive that you previously loaded, click the Registry menu, and then click Unload Hive.
Quit Registry Editor.
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