First go to the start menu and right click on "My Computer" and select properties.
If you're using Windows 8 you can press "Windows + X" and select 'System'
Next click on either 'Remote Settings,' 'System Protection' or 'Advanced System Settings' on the left side of the window
Then click on the Computer Name tab on the top of the Window and then click 'Change...''
Lastly check if you're a member of the domain. Windows computers will always be setup as a workgroup by default.
If you're not on the domain change it and type in 'soest.hawaii.edu' although you will have to restart your computer
for it to take effect
After you restart you should notice that your computer name will be in front of your username followed by a backslash when you login.
Login with .\USERNAME if you want to login with a local account and login with SOEST\USERNAME if you wanna login with your SOEST account.