If it is a new BDC, and you have already added the BDC machine name, delete it. Recreate it using the Windows 2000 Directory Manager snap-in:
Start ADSI Edit and view the userAccountControl property for the new computer object.
Change the value of the userAccountControl object to 8192 from the default of 4128.
After this, you should be able to install the Windows NT4 BDC. Now the Windows 2000 PDC will recognize that the machine account (ends in $ as in waynespc$) is a computer object not a user object.
Taken from Q221826 . Check to see if there is updated information or other workarounds. Microsoft periodically updates these KB articles.