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This was using OS X's Disk Utility. I accidentally repartitioned my 2nd Windows drive (to Mac OS Extended [Journaled] and GUID Partition Table). It seemed pretty immediate, so I'm assuming there was no real 'erasing' going on.

Is there any way to switch it back to MBR & NTFS, keeping all my files and programs intact?


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As with every time this question comes up - I'd suggest giving testdisk a shot - if its a quick format or similar, as opposed to a wipe, it will very likely be able to see and restore the previous partitioning.

As with any recovery operation, i'd suggest imaging the disk first, since then you can try a variety of recovery methods.

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Thanks, I'll give it a shot. – incarna Feb 19 '12 at 3:44
This was probably the best shot I had. Wasn't successful but I'm going to keep trying, thanks. Hope I was doing everything right, though. I was following the docs the best I could. – incarna Feb 19 '12 at 11:29
If it didn't detect the windows partition, then well, it apparently got wiped. I've followed the guide and its worked perfectly the few times i needed to fix a situation like this. – Journeyman Geek Feb 19 '12 at 11:58

From my limited experience with this I will try to provide advice. As long as you didn't reformat you're drive to a different file system, changing the partition entry in the partition table shouldn't be a problem. The real issue here is you changed from MBR to GUID, meaning it probably erased some important data, since they do not use the same exact areas of the the harddrive to store partition data. So the real answer is without some serious work on you're part, it might be very difficult. When you repartition your harddrive you don't really actually erase anything, you just change the partition table, which in this case can be destructive.

Also if you did not click apply in Disk Utility, it will have done no conversion any way, so you should be alright.

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I did apply the change. :( Any guidance on what I can/should do if I want to try to get my stuff back? Or is it nearly impossible? There isn't too much important data on there, but all of my secondary programs are installed on there so it would be a huge hassle to deal with. – incarna Feb 19 '12 at 3:41
Journeyman posted a good link I checked it out. – rubixibuc Feb 19 '12 at 3:54

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