On Windows 7, Windows Vista, and Windows XP

• 1). Select "Start" from the Windows desktop. Select "All Programs." Select "Accessories." Select "Command Prompt."
  
  
• 2). Type ipconfig and hit "Enter".
  
  
• 3). Locate the line that says "IPv4 Address" under the network connection you are troubleshooting. The address is the number listed on that line that is in a format similar to ###.###.###.###
  
  

On Macintosh OS X 10.5

• 1). Open the Apple menu in the upper right-hand corner of the desktop screen. Select "System Preferences" from that menu. Select "Network" from the "System Preferences" menu.
  
  
• 2). Select the "Ethernet" network on the list of networks displayed on the left hand side of the screen.
  
  
• 3). Note that the TCP/IP address of the computer will be displayed on the line that reads "IP Address:."