The release notes ("RELEAS.NOT" on diskette #4) of the DECnet/DOS v1.1 on bitsavers http://www.bitsavers.org/bits/DEC/decnet/ has a bunch of comments about the Rainbow. Was there a separate release for the Rainbow?? You're right that the RX50 diskettes in the Rainbow weren't PC compatible, so it could simply be different media. Bob