15 Problems That Your Plague Your PC
And How to Solve Them


--by Karen Kenworthy, Contributing Editor, Fred Langa, Senior 
Consulting Editor, John Woram, Consulting Editor, Serdar 
Yegulalp, Technology Editor


** Problem No 15: I can't log on to the network. **

Solution:
With so many components in the chain-NICs, cables, 
hubs and OS drivers-troubleshooting network connections is 
never easy. You have to approach the problem systematically. 
First, check the obvious. Make sure all cables are securely 
connected to their ports in the NIC and hub, link /activity 
lights are on, and all equipment is compatible (i.e., 10Mb per 
second NICs with 10Mbps hubs, 100Mbps NICs with 100Mbps hubs). 
A lot of equipment can operate at both 10Mbps and 100Mbps, so 
if the equipment doesn't autosense the speed, make sure you 
manually set it on all devices in the connection. Some older 
auto-sensing 10/100Mbps NICs choose a speed, and are locked 
into it until you power down and back up again. So if you 
manually switch hub speed from 10Mbps to 100Mbps and experience 
problems, turn off the machine with the NIC and turn it back 
on again.

The cable may be your problem, even if all link/activity lights 
are on. Ethernet wires are crimped into RJ-45 jacks, and they 
can slip enough to break the connection. Test them with an 
Ohm/Power meter set to indicate when there's continuity between 
the pins on each side of the wire. This also helps you verify 
the wires are pinned straight through, not crossed.

If all's well on the physical side but problems persist, use 
WINIPCFG.EXE (IPCONFIG.EXE in NT) to ensure the OS knows the 
NIC is operational, and that the proper protocols (IP/IPX and 
so on) are loaded and bound to the NIC. NICs that aren't loaded 
properly won't show up here. If everything checks out, use 
PING.EXE to test communications with other machines (preferably 
local) using TCP/IP, or with machines that are reliably up on 
the Internet (make sure you dial into your ISP first). For 
instance, "ping ftp.somewhere.com" will report a series of 
"reply" messages with response time in milliseconds. If you 
know the actual IP address (www.xxx.yyy.zzz) of the machine 
you're trying to reach, use that instead of the qualified 
domain name. This eliminates the possibility of a faulty DNS 
setting. If you don't know one, ping a server by name and ping 
will give you the IP address. If pinging an IP address doesn't 
work, remove the NIC's network configuration entry and reboot. 
Windows should recognize the NIC and reinstall it for you. You 
may need to reinstall and reconfigure your TCP/IP protocol 
settings as well.


 1998 Windows Magazine, April 1999, Page 112.