Question : what is netbeui?

My loopback ping doesnt work. They tell me it is because my netbeui doesnt work. So what is it, why has it disabled my pinging and what else will be disabled if i turn it off?

Seb

Answer : what is netbeui?

NetBEUI is an enhanced version of the NetBios protocol that is used by Microsoft Windows networking. It is a non-routable protocol, which means that computers that are not located on the same network segment or subnet can't communicate.

1) You are using the "Multiple IP" method of sharing.
In this case, you don't have the option of following the instructions in Item 2, since all of your computers' Network adapters must use TCP/IP and they are all connected to the Internet.  If this is your situation and you must share Files and Printers, then you definitely should use NetBEUI for File and Printer sharing, and have strong password protection  on anything you share.

2) You have separated your LAN from the Internet, but you have opened ports or have placed a computer(s) outside your Sharing server's firewall in order to use certain applications or services.
If you are using some method other than the Multiple IP method to share your Internet connection, you have the protection of a separate network and a firewall or proxy.

If you're using a hardware router, you don't need to do anything further.  If you're using a software NAT-based router like ICS or Sygate, as long as you unbind Client for Microsoft Networks and File and Printer Sharing for Microsoft Networks from the copy of TCP/IP that is bound to the network adapter that connects you to the Internet, you're secure. In both these cases, you don't really need to use NetBEUI for File and Printer sharing unless you like a "belt and suspenders" approach.

However, once you start poking holes in a NAT firewall or adding TCP or UDP mapping services to a proxy server, you are making direct connections to your LAN for at least some data from the Internet.  If you open the right ports (TCP or UDP ports 137, 138, and 139), you will allow access to your LAN's computers from the Internet if you are using TCP/IP for File and Printer sharing.

In this case, you should use NetBEUI for File and Printer sharing.

Turning it off might affect things depending on what OS, network etc you are on.