CD-RW drive only reads some files

I burned some CD-RW discs a few years ago, using my HP 7510e parallel connected external Multi-Read CD-RW drive, fed by my laptop, using windows 95 and the HP software. On my new machine, running XP, and using Iomega Burn & Go Gold, (finally gave up on bundled crap), only some of the files on those same old discs are recognized when inserted into my LG CD-RW drive, but all the files are recognized when inserted into my Samsung DVD drive. Any ideas why?

I burned some CD-RW discs a few years ago

I’m surprised they are readable at all. RW discs are not long-term storage tools.