I have 3 pretty standard WIntel boxes, plus a newly setup multi-boot #4 with 3 OSes, all connected via ethernet switch by TCP/IP to operate under one same workgroup.

Booted in 98 SE or XP Pro+sp2, Box #4 Network Neighborhood sees all 3 others, and vice versa, and data transfers perfectly between all.

However, booted in NT4 Wks+sp6a, Box #4 Network Neighborhood sees none of the 3 others, and vice versa, thereby data can't transfer between Box #4 and any other.

Also, booted in NT4 Wks+sp6a, Box #4 fails to ping any of the other 3 boxes, whilst on the contrary all 3 others succeed in pinging Box #4.

Where does the problem possibly lie? Any directions will be highly appreciated. TIA!

First and foremost do you have the correct NIC drivers installed on the NT4 Box??

Did you reapply SP6 after you installed the NIC card? If not do so.

Thanks! I believe I have correct NIC drivers, and I do reinstall sp6a after every move. Box #4 has onboard Intel PRO100+ Management Adapter, and I fed it with Intel's latest driver v9.2, and in NT4 Intel's diagnosis shows PASS for all items. Actually I also tried several other add-on NICs including Intel, 3Com, Dlink, Realtek, with latest version drivers, all worked well in XP and 98SE but not NT4.

Are they all on the same subnet, i.e IP 192.168.0.1-4 SNM 255.255.255.0?

In the same workgroup or domain?

Can you ping the loopback address? 127.0.0.1

Thanks! Same subnet and workgroup, and pings loopback fine.