When I try to open my backup of my project I saved to a flash drive (compressed file), I get an error message that says “Please insert the last disc of the multi-volume set and click OK to continue.” I cannot open the file. Have you seen this before?
If you’re trying to open the zipped backup using Scrivener, that won’t work. First unzip the project folder, then double-click the .scrivx file to launch the project in Scrivener.
If you’re trying to open the zipped backup file using Windows Explorer, it sounds like Windows thinks the file spans multiple usb sticks. Did you save this one yourself? Does it span multiple usb sticks?