I just had an interesting experience when adding a new recording drive and backup drive to my system (a Power Mac Dual 2 GHz G5 running OS X 10.4.7). I partitioned the drives in order to create a separate area for storing my samples and loops. I used Apple’s Disk Utility to do the partitioning, and all seemed to go smoothly. After copying all the data to the new drives, I opened up Pro Tools LE and when I hit Play, nothing happened except for an error message “DAE Error-9131″.

I thought perhaps it was something about that particular song file, so I opened another one, but the same thing happened. I wondered if perhaps my new drive wasn’t supported by Pro Tools, but that seemed unlikely. So I got on the Web and started researching it. It turns out that there’s a preference hidden in the Options section of Disk Utility that selects a partition scheme, and for some reason it defaults to “Master Boot Record,” which is designed for drives that will be used “to start up DOS and Windows computers, or to use with devices that require a DOS-compatible or Windows-compatible partition.” Why this is the default is mystifying to me.

Apparently, disks partitioned with this scheme are not compatible with Mac Pro Tools systems. So I chose the “Apple Partition Map” option instead, and had to repartition the drive (and, of course, re-copy all the data. What fun.) After doing so, my Pro Tools sessions worked fine. The moral of the story is: check the Options tab in Disk Utility before you partition a drive. BTW, my research also revealed that if you have an Intel-based Mac, you have to use a different partitioning scheme, the GUID Partition Table. For more info about partitioning schemes, go to this page from the Apple Developer Connection site. Also check this page, which I found cached on Google from the Digidesign site.