How to use files with -arc after the extension?

[saunassa]

I have to do some work on a customers old board designs. My problem is with file names and errors. the files have a -arc after the extension. An example is 54312.Max -arc
the same holds true for the DSN file too. I have so far used a variety of compression tools to no avail with the closes to working being freearc.

Any suggestions? when i looked in the file using word I see a reference to Orcad 9.00