It’s Christmas, and besides the usual Christmas stuff, this time of year is back up time for many people since it’s never done during the year. So you got your external drive (a Maxtor 500 gig USB drive in my case) from Santa, plug it into your laptop, format it and then you start to back everything up: Documents, pictures, music, movies etc…

But then you hit a big file, which starts to cause problems: The hard disk images from your virtual machines (e.g. WinXP.hdd using Parallels). You’ve formatted the drive using FAT32 in stead of NTFS so you can access it from most OS’es but when you try to copy it to the external drive you get a (useless) error message on OS X, more specifically

Operation cannot be completed, error code -1309.

The problem is the formatting of the drive. FAT32 does not support files larger than 4 gigabytes. I google’d around and found this in a forum, which explains that it’s time to open the Terminal and using split command. So I did. My .hdd file is around 9 gigabytes in size, so 3 files of 3 gigabytes should do. But no, running the split example mentioned in the forum only gives you another (useless) error message:

split: write: Invalid argument

You thought you had it fixed, but no. But hang in there, the solution is near! As I found in this Mac OS X hint, this error occurs because Apple “is shipping an older copy of split” which restricts the file size of the split files to less than 2048 megabytes. So, to fix all your large file backup problems, use something like

split -b 2047m winxp.hdd /Volumes/MAXTOR500GB/MacBook/Parallels/winxp.hdd.

where the last . automatically appends .aa, .ab etc.