Update Nov 19, 2009
— I just came accross an open source piece of software that might do all of the manual work described below for you. It’s called TestDisk, open source data recovery software.
I haven’t used it, but it looks very promising! —
Original article, Jan 4, 2008
Say you’ve got an external harddisk in a Firewire or USB enclosure. It’s Apple Partition Map (APM) partitioned and contains a couple of HFS+ Journaled formatted volumes. You’re happily using it on your Mac and for some reason you’ve decided to hook it up to a Windows PC. You’ve installed MacDrive on it, but somehow it doesn’t recognize the volumes that are on it. You check the Disk Management tool and you notice a red stop sign on the external drive. When you right-click the symbol, you’re able to “initialize” the drive. You hesitate for a second, but decide it must mean something like “just start the damn thing up, so that it works” (later on you know that this must have been your weakest moment of that day, maybe even the entire week, but at this “moment suprême” you feel it’s the only choice). And then, disaster strikes. Cause “initialize” means something entirely else. The Disk Management tool has just overwritten the APM with a Master Boot Record (MBR) and all partition information seems lost.
That is exactly what happened to me last week. After extensive searches on the internet, the only option seemed to be to buy and use a data restore/recovery program like Disk Warrior II, which meant copying/restoring/recovering the full 250GB of info to another harddisk, which I don’t have. It seemed wrong, the only thing gone was the partition information, the data was still there, why should I spend money on: a) software; b) hardware; to recover “undamaged” data?
Then I found this post on Ubuntuforums.org and it made me see the light.
Before you start doing anything I recommend reading through all below-mentioned steps and then decide whether you can do this. Furthermore note that the disk I used was originally partitioned using an Apple Partition Map. Recent (Intel) Macs have been formatted using GUID Partition Table (GPT) and I have no clue at all whether this will work on GPT drives.
Continue reading Restore an Apple Partition Map