This feels related so I will try here. I have Diskwarrior 4.1.1 installed on both partitions of my Macbook Pro's drive.

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(Backstory: I've got a 250g drive, split into a 230g working volume and a 20g rescue volume. Also have Drive Genius on both. When I want to run either, I'll restart from the rescue volume, run repairs/rebuilds on the working volume, then restart back into the working volume. Saves a lot of time, and I can also clean up 'rescue' from 'working' from time to time.) If I'm in 'working', I can fire up DiskWarrior fine (it asks for my password), run it on 'rescue', and all's well. But when I restart in 'rescue' in order to clean up 'working,' launching DW results in 'unexpected error - be sure to mention -120' (words to that effect), and then quits. Both volumes have 10.5.6; both run Drive Genius fine on each other. Any thoughts on why DW would run ok from one partition to the other, but not the other way around?

Jan 29, 2009 4:54 PM. I am copying what was sent to me from Alsoft about Diskwarrior. This maybe the solution.

You have a 'revision 42' DiskWarrior CD (which contains Mac OS X 10.4.x Tiger) but this computer requires at least a 'DVD revision 810' (which contains Mac OS X 10.5.x Leopard) to start up from a DiskWarrior disc. When Apple releases new hardware, a newer version of the operating system is required to support all of the hardware features that have been added. In most cases, older DiskWarrior 4 discs cannot start up newer machines because they do not have the necessary System files. The downloadable updater modifies the DiskWarrior application - it does not update the operating system on the CD. As your original DiskWarrior disc does not start up this computer, neither will the disc that you have created using the downloadable updater. As stated on the Alsoft website, and in the ReadMe file which comes with the updater: 'Please note that the new startup disc you create will start up the same set of Mac models as your current DiskWarrior disc.

Your new disc will not start up any Mac that your current DiskWarrior disc can not.' The DiskWarrior 4.1.1 (DVD revision 901 - newer than the 810), which contains an operating system capable of starting up this MacBook 4,1 is now available. Please contact our Sales Department to purchase an updated DVD. Installer User Interface Mode Not Supported Ubuntu on this page. They can be contacted at 1-800-257-6381 (US Toll Free) or at 1-281-353-4090 (International). You can also email them at 'sales.info@alsoft.com', if you prefer. The updated disc is around $20 shipped.

Alternately, you could utilize one of the following configurations to use your current DiskWarrior 4.1.1 CD. (1) Alternate Startup Disk: If you have an external drive such as a FireWire or USB2 drive (Intel-based Macintosh only, formatted with the GUID Partition Scheme) or a secondary internal drive or partition, you could install OS X (the version which shipped with your computer or higher - must be Mac OS X 10.4.x 'Tiger') on that drive and then start from it. Install DiskWarrior into that drive's 'Utilities' folder, (which is inside the 'Applications' folder) and run DiskWarrior from there. (2) Target Disk Mode: Connect two Macs with a FireWire cable where the one is the 'host' and the other is a 'target'. The host Mac should be running OS X (10.4.x 'Tiger' or higher). In this scenario, the target Mac is the MacBook 4,1 that cannot be started from the DiskWarrior disc.