Although it's true that it's disabled by default, it is still possible to join MCE computers to a domain. I have two Media Center boxes joined to the domain on my network. What you need to do is change the SYSTEM registry key WPA|MedCtrUpg|IsLegacyMCE to a 1 (one). It's a little more complicated than running regedit, but it's still pretty simple to do. Here's how (posted from http://www.combobulate.com/node/18
, but I've found it other places as well):
1. Insert any Windows XP CD.
2. Boot to the CD and choose 'Recovery Console'
3. Select the installation to log onto (default: 1) and press
Enter. (Most likely the administrator password will be blank. If
it is not enter the password you set or contact the manufacturer.)
4. Type cd system32\config and press Enter.
5. Type copy SYSTEM c:\ and press Enter.
6. Type exit and press Enter.
7. Boot the PC back into Windows
8. Start > Run > Type: regedit and press Enter.
9. Click on 'HKEY_LOCAL_MACHINE'.
10. File > Load Hive...
11. Browse and select C:\SYSTEM
12. Specify key name 'TEMP' and click OK.
13. Expand: HKEY_LOCAL_MACHINE > TEMP > WPA > MedCtrUpg
14. Change the IsLegacyMCE value to 1 and click ok.(one, not an L)
15. Click on TEMP subkey (under HKEY_LOCAL_MACHINE).
16. File > Unload Hive. Confirm.
17. Reboot the PC.
18. Boot into the Recovery Console using the Windows CD again
19. Select the installation to log onto (default: 1) and press
20. Type cd\ and press Enter.
21. Type copy SYSTEM C:\WINDOWS\SYSTEM32\CONFIG\SYSTEM and
press Enter.(Choose 'yes' to overwrite)
22. Type del SYSTEM and press Enter.
23. Type exit and press Enter.
24. Boot up Windows.
25. The 'Join Domain' option should no longer be grayed