Here's an interesting one...

My company recently upgraded some network components. We removed a 24-port 10MB Netgear Hub and replaced it with two 16-port 10/100 Linksys Switches. After connecting the systems to the switches, about 95% worked perfectly. The other 5% lost sight of the network. Here's what I know...

The network is a TCP/IP network running all Win9x systems.
The systems that are affected use a CNET Pro120(b) 10/100 NIC. (This same card & driver version are used in other systems that do work) I have connection lights on both the switch and the NIC to the systems that are not working. I cannot browse or ping any system on the network. The systems can ping themselves.

Here's the real confusing part...
If the speed setting is manually set to 10MB Full-duplex, the system works perfectly. It will browse the network and perform all normal functions. If the speed is set to automatic or any other manual setting (100MB half-duplex, etc.) then the system stops seeing the network again.

Any ideas?

Thanks in advance.