Waiting for Disk Copy Helper

[Dale Hoffman]

After installing QuickTime 6.5.1 Pro and restarting, I was unable to 
mount another DMG file. The Disk Copy Progress window shows "waiting 
for Disk Copy Helper" but Disk Copy fails to mount further DMG files.

I try to drag DMG files onto Disk Copy without success - same error.

Error message: "Unable to load the disk image driver. Error -536870208.

I've run searches on Apple's Support site and thought I'd ask here 
before calling Apple directly.

Mac G4, OS 10.2.8

DaleH