Another hyper-technical FilmHelp computer post from Greg Pak
While undertaking the mind-blowingly nerdy task of updating a 1995-era PowerBook 190 from OS 7.5.2 to 7.5.3, I discovered that my Mac Pro (running OS 10.6.1) would read a Zip disk in an external USB Zip drive — but it would not write new data to that same disk.
After doing some poking around, I found this helpful post that explained that Snow Leopard has disabled the ability to write to HFS-formatted disks — which was the standard when this Powerbook was produced.
In practical terms, that means to get files from my Mac Pro onto the PowerBook 190, I had to transfer them to a G4 desktop via a USB drive. Then I transferred them from the G4 to a Zip disk. And then transfer from the Zip disk to the Powerbook 190. Whew!