I need help solving a problem with my G4 MAC's USB. I recently upgraded my operating system from 8.6 to 9.1 because I was having stability problems. The upgrade was successful and seemed to solve my stability problems. Unfortunately it seems to have created a new problem. Specifically I am no longer able to get any USB device that mounts a volume to work. Specifically my Imation Super Disk Drive for floppy disks and my digital camera to download pictures. Before the upgrade to OS9.1 they both worked fine and mounted the disks on the desktop, now nothing mounts. All other USB devices such as keyboard, mouse, CD burner, etc. work fine. At my work I have access to a similar G4 also running OS9.1. I copied it's extensions folder and took it home and compared it to my home computer. I copied from it to my home computer's extensions folder any extensions not present, but nothing changed. I would appreciate any help anyone can provide as I am out of ideas. Thank you, Eric . . . . .