Join Client System in a Domain
Right click my computer- properties.
Select computer name tab.
Select domain option and type your domain name after it will ask user name and password.
Type server administrator user name and password.
After you can see computer name with domain name and domain name. Click apply and ok button.
After restart the above dialog box appears, you press ALT
Now you can log in to domain after typing user name and password by clicking log on to drop down box and selecting your domain name click ok.