A domain can be a great way to help administer networks that want to share resources whether it be files, printers or other services. When you have a large number of workstations it can get very annoying having to authenticate with servers when you want to access file shares or printers. This is where a domain comes in, once you have logged into your computer you will be authenticated with the domain, any further authentication attempts will query your username and permissions, so no more annoying username and password prompts!

But anyway, joining a domain is a pretty simple task and I’m going to show you how to do it with Windows XP, and Vista / Windows 7. First up, windows XP.

How to join a computer to a domain in Windows XP – Firstly find the ‘My Computer’ icon, it is probably on your desktop, if not it should be on the start menu. Right click on it and choose properties. Now, click on the ‘Computer Name’ tab and then look for the button next to the ‘To rename this computer or join a domain, click Change’ label, it should be called ‘Change’ funnily enough. Click it! You should then get this dialog box:

Now, click the domain box and enter your domain name, all being well you should be prompted for an administrators username and password to join the domain. If this hasn’t worked then chances are your DNS servers are either incorrect or not properly configured. Depending on how your DNS and DHCP is setup you might also want to click on the ‘More’ button and enter your dns suffix in that box. For example if your domain was called domain.com then your computer would want to have the fully qualified domain name of computername.domain.com.

Once you have entered the username and password you should receive a message box welcoming you to the domain, you should now reboot and login for the first time once your machine is back up.

How to join a computer to a domain in Windows Vista and Windows 7 - Good news, the above process is exactly the same in Vista and Windows 7! There is a slightly different way of getting to that dialog though. If you right click my computer and choose properties you are now looking for the ‘Advanced System Settings’ button the left. Then click the ‘Computer Name’ tab and you will be presented with the computer name details box. Again, click on the ‘Change’ button to enter the domain name in there followed by the administrator username and password.

It is worth noting that not all versions of Windows can join a domain, for example Windows XP Home cannot, and neither can you do it with Vista home basic or Windows 7 home basic.