Putting a folder at the root of the external and adding additional data there won't have any effect on the bootability of the the external drive. Depending on how you're doing the mirroring though . . . you'll need to make sure that your software (SuperDuper, PSyncX, Disk Utility, CarbonCopyCloner, whatever) is set to not delete files from the destination . . . otherwise since the extra folder at the root of the external isn't on the internal it will get deleted. On Mar 29, 2008, at 12:18, Said Nuseibeh wrote: > Hi Listers, > > If I mirror my g4 laptop (10.4.11) on a bootable external FW drive > that > has greater hard drive capacity, and I want to use that remaining > space > to incrementally store new data, where should I put that data so as > not > to interfere with system operations if --in the case of mishap-- I > ever > have to boot from that external disk?