Try JCMD, it simulates many DOS commands at the console prompt. Filer.nlm is a file manager designed to allow network administrators the flexibility to access Netware and DOS file systems from a Netware 3.x or 4.x file server console. This indicates Bad Packets. The first place to look at is your wiring plant. The checksum is at the very end of each packet and that's the place least likely to be damaged in transit unless the system is well out of spec.
Damage can be subtle, enough so to pass the hardware CRC check since software is also involved.
Lest folks think I'm just talking, have a look at an serious IP machine and see the errors revealed by netstat. I provide my student lab consultants with a show and tell on lan wiring. I demo ordinary packets with a good Tektronix sampling scope, plus variable attenuators, coax stub extensions, inserting another kind of coax, etc. Thus squeezing wires in a bundle increases NEXT, a very bad thing. Transmitted data goes on one pair, received data on another.