Reading multisession CD-RW on PC with packet writing

On one PC I use Nero 5.5.x.x to write files to CD-RW using Nero
5.5.x.x in multisession mode, updating the changed files till the
CD-RW fills up. On another PC I pop the updated CD-RW into a CD-ROM
drive and copy the files off to the hard drive without problems. This
has been working fine for years.

I just installed a DVD writer on the second PC and I also installed
the Pinnacle InstantWrite packet writing software that came with it.
I have InstantWrite enabled on the DVD writer but not on the CD-ROM
drive. Now when I pop the CD-RW into the CD-ROM drive all I can see
are the files from the first session. None of the multisession updates
show. Makes no difference if I turn InstantWrite on or off on the
CD-ROM drive, it's the same. If I take the CD-RW to another PC nearby
I can see the updated files just fine.

Any ideas what's going on here? (Pinnacle hasn't answered yet. I tried
replacing InstantWrite with Ahead InCD and InCD caused other problems
on the DVD writer that I could not tolerate so it's gone . . .)


George