I was able to open FM3 files (from 1992...) in FM9, without any problems/messages, so it may indeed (unfortunately) indicate that something is wrong with the files themselves.
Here is a sample FM3 file, in case you want to try opening it in your system: http://www.microtype.com/resources/FM3-RELNOTES.zip Shlomo Perets, http://www.MicroType.com FrameMaker training & consulting
