Computer Name

• Each computer on the network has a name with a length of up to 15 characters. The naming system allows any combination of letters and numbers but forbids spaces and a few other special characters. A protocol known as NETBIOS stores the name and uses it when communicating with other computers. If two computers on the same network have the exact same name, it causes a conflict.
  
  

Consequences and Resolution

• If you have a NETBIOS name conflict, the second computer with the conflicting name cannot access the network. You can log into the computer and use it as a stand-alone machine, but you cannot share data or devices with other computers. To connect the computer to the network, you must first give it a unique name. Right-click the "My Computer" icon, select "Properties" and click on the "Computer Name" tab to change the name. If it appears that the name is not a duplicate of any others on the network, the computer may have a network adapter, IP address or other problem.
  
  

IP Address and Network Adapter

• A conflict of Internet Protocol addresses may cause the name conflict. At a command prompt, type the following commands to clear the IP address and obtain a new one:
  
  ipconfig/release
  ipconfig/renew
  
  If the computer has had its network adapter card replaced, the old software drivers may cause a problem. Right-click the "My Computer" icon, select "Properties" and click the "Hardware" tab. Click the "Device Manager" button, pull down the "View" menu and select "Show Hidden Devices." Open the set of devices under Network Adapters by clicking the + symbol, and look for any adapters that have transparent icons. Uninstall these adapters, close the window and log into the network.
  
  

Old Software

• For computers running older versions of Microsoft Windows, such as Windows 2000 and Windows NT, a NETBIOS problem can cause duplicate name conflicts. The issue may also appear as intermittent problems connecting to other networked computers. To solve this problem on Windows 2000, download and install the latest Service Pack for the operating system. For Windows NT, Microsoft has a hotfix file, Q269239i.exe, that you download and execute on the computer.