3Com 3C509B (10 mbit Ethernet combo card)
NT4 SP6

After turning on PC, the NIC LED is continuously active UNTIL about 5s after the NT logon-screen has loaded. Then it darkens and shows no more activity. There is no network connectivity. Only when turning the PC completely off and back on, the LED will be active again. A simple <ctrl><alt><delete> doesn't "wake" the NIC.

What I did:

- re-installing drivers
- fixed UTP instead of auto-detect coax or UTP
- other HUB-port and even entirely other hub/switch
- other cable
- other wall outlet
- ping 127.0.0.1 is ok
- assigning a static IP address to the PC and pinging it is also ok, other Ips get "timed out" errors

Via 3Com diagnostics software, the "NIC test" is completed successfully. Network test doesn't succeed, though, and the statistics show that all transmitted packets have "carrier sense lost" errors.

What's up here???

Any ideas appreciated.
TIA,

Jo Helsen

Answering to my other mail in this thread. After going through a seemingly endless number of permutations, I solved the problem :-) . It seems like it was a very unlikely combination of multiple faulty and/or badly connected cables. One came straight out of the package and I am almost sure that it still worked the first time???

You have to be very carefull when interpreting "ping" results as well, it seems!!! When doing a ping _ipaddress_ -t and switching cables, sometimes replies keep coming, sometimes you get an interruption. Sometimes you only get replies again after interrupting the ping and starting it again etc..etc.. A few times I got the impression that I used even *more* faulty cables or that half my switch and hub-ports had failed <G> Are there any rules of thumb for when happens what?

JoH