Remotely join PC to domain

With a VPN account you can join a computer to the domain remotely. The basic steps, for Windows XP, are:

1. Set up a normal VPN connection and make it available to all users.
2. Edit the VPN connection to enable the "Include Windows domain" option.
3. Join the computer to the domain but don't restart it yet. (You might need to add the appropriate DNS server to the TCP/IP properties of the VPN connection so that it can resolve the domain.)
4. Open User Accounts(*) in the Control Panel and add the domain administrator as an administrator of the computer.
5. Restart the computer.
6. At the login screen, check the "Logon using dial-up connection" box and enter the domain administrator details. Choose the VPN connection.

You'll then be logged into the PC as the domain administrator and can finish setting up the PC.

(*) If opening User Accounts isn't showing you the right interface, invoke it by running this command:

control userpasswords2

There are a few differences with logging-on via VPN, with later versions of Windows:

• Vista: At the logon screen, click "Switch User", then click the blue icon.
• 7: Log into the local computer, connect to the VPN, then choose "Switch User". You can then logon using domain credentials. Alternatively, use the older-style login screen and click "Switch User", then click the blue icon.
  

Idea credit to Marina Roos.