1. Click on the "Start" button and "Run" in Windows XP/Vista; hold down the Windows key and "R" at the same time in Windows 7.
2. Enter "cmd" in the run box and click on "OK."
3. Wait for the DOS prompt box to open. Type in "ipconfig/all "at the prompt and press "Enter."
4. Scroll down until you see the listing for "DNS Servers." Record the numbers listed there. They will be appear similar to "192.178.1.1."