Bring up the System Properties either from Properties on My Computer or from System in Control Panel
Click the Computer Name tab
Click Change…
Click More…
Ensure Primary DNS suffix of this computer is correct
Ensure Change primary DNS suffix when domain membership changes is unchecked
Click OK
Enter the new domain name in the Member of group under the Domain textbox
Click OK to ack “Welcome to the new.domain.com domain” popup window.
Enter your new.domain.com id and password
Click OK
Click OK to the “Reboot Required” message box
Click OK
Click Yes to reboot
Once rebooted login with your new.domain.com id and password.
Logoff
Login as Administrator on your Computer
Right click on my computer, select ‘manage’
select “Local Users and Groups”, then “Groups” and right click on Adminstrators (and choose Add to Group..)
Enter your user name, check name, OK
Navigate to C:\Documents and Settings in Explorer
Bring up the folder properties of your old %USERPROFILE% Noted in the first step
Click on the Security tab
Click on Add…
Type in your new.domain.com id and Click Check Names
Enter your new.domain.com id and password
Click OK
Click OK
Click Full Control
Click Advanced
Make sure Replace permission entries on all child objects is checked
Click OK
Run regedit
Click on HKEY_USERS
Select Load Hive… from the File menu
Navigate to C:\Documents and Settings in Explorer
Click on your old %USERPROFILE%
Enter NTUSER.DAT
Click Open
Enter an easy to remember Key Name like disco
Expand HKEY_USERS !TreeNode
Right click on disco key and select permissions
Click Add…
Type in your new.domain.com id and Click Check Names
Enter your new.domain.com id and password
Click OK
Click OK
Click Full Control
Click OK
Click on disco key
Select Unload Hive… from the File menu
Click Yes
Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\!CurrentVersion\!ProfileList and expand that node
Find your new %USERPROFILE% by looking at the !ProfileImagePath key (it may end in something like .NEWDOMAIN)
Double click the !ProfileImagePath found above and change it to end in your current %USERPROFILE%
Find !ProfileImagePath with old %USERPROFILE% key and dbl click and change it to append a .old
Exit regedit
Open explorer and navigate to the folder one above %USERPROFILE% (typically C:\Document and Settings), rename any folders that end in NEWDOMAIN domain to OLDDOMAIN (must differ from reg key setting above)