One of our users inquired about >50 MS Project 4.0 files dating back from 1996.
Our current Project version is MS Project 2003, and that is unable to open the old files. We were also unsuccessfill in installing MS Project 98 and MS Project 4.0.
So I tried to open the files with OpenProj, but that didn't work either. However I have good hopes that this will be easier to fix than with MS Products.
If you need an example file, I can send it in private mail, but I'm not going to put it online because it is internal business information.