While digging around TechRepublic's Technical Q&A, I recently came across a question from member Pcquestwho is experiencing an all too common problem with the Windows 95 machines she supports. When booted, the workstations often fail to recognize the network.
After investigating the problem, Pcquest discovered that the machines weren’t receiving an IP address from the network's DHCP server. Knowing this, she was able to manually acquire an IP address using Winipcfg's Renew command. When the machine was rebooted, it attached to the server. However, this is only a temporary solution and according to Pcquest, "This [problem] happens quite frequently."
So what's causing the problem and how can Pcquest permanently solve it? I’ve run into this problem many times over the years and have found that—unless there are network or server problems—the NIC is often the offending device. If this is the case, you have three options: Update the drivers, replace the NIC, or try a static IP address.
Update the NIC drivers
Before trying any other troubleshooting techniques, make sure the latest NIC drivers are installed. I once supported a group of PCs running OS/2 Warp that connected to NetWare servers. The PCs would initially connect to the network with no problems, but after what seemed to be a random time (from five minutes to three hours) the machines would drop the connection. I worked on this problem for quite some time before I discovered that the 3Com drivers used by the PCs were a little buggy. After I updated the drivers, the problem disappeared.
Beware of generic NICs
While not all generic network cards are bad, it's been my experience that a cheap NIC is often to blame for network connection problems. For years I've used generic network cards from a company called Encore, and while I have had very few problems, Encore cards tend to be the exception rather than the rule. Most of the other generic NICs I’ve used have had lots of connection problems. In the end, I usually get frustrated and replace the generic NIC with one from 3Com, D-Link, NETGEAR, SMC, or Linksys.
A static IP—your last resort
But what if a driver update doesn't work and you aren't able to replace the NICs? I once faced such a dilemma when a client, who was suffering this problem with several Windows 98 SE workstations attached to Windows 2000 servers. I was certain that replacing the network cards would solve the problem, but the client refused to pay for new cards. I had to come up with another solution.
Because the problem was the acquisition and renewal of IP addresses from a DHCP server, I was able to solve the problem by assigning each PC a static IP address. Switching to static IP addresses didn’t completely resolve the issue, but it greatly reduced it. Usually, when someone was unable to connect, they could simply reboot the machine and it would connect on the next try.
However, there were two machines in the facility that never seemed to work right, even with static IP addresses. One day, I had a couple of spare name brand NIC cards that were left over from a job in one of the client's other facilities. I secretly switched the generic NICs on those two machines with name brand NICs and the problem went away.