Hi all, Sorry mods if this is in the wrong section, please feel free to move it if it is! I need a bit of help with my external hard disk that was primarily used with my old PC... It has two partitions on it, one NTFS and the other FAT32, and I basically wanted to erase everything that was on it to make it compatible with my Macbook Pro (currently running OS Snow Leopard). I used Disk Utility on the quickest erase setting to format it and it went through successfully. However, I noticed that it wasn't able to remove some invisible files that was still on the disk (it showed it had a usable disk capacity of 39GB but it had 100MB used for no reason after the format), so I ran Disk Utility's erase function again, but this time on the most thorough setting (I forgot what it's called, but it's the highest secure erase option). The process failed and displayed an error: 2012-01-03 11:15:49 +0000: Mounting disk 2012-01-03 11:15:50 +0000: Erase complete. 2012-01-03 11:15:50 +0000: 2012-01-03 11:18:28 +0000: Preparing to securely remove data from disk : IBM Travelstar 2012-01-03 11:18:28 +0000: DOD Compliant 7-Pass Secure Erase (DOD 5220-22 M) 2012-01-03 11:47:03 +0000: Secure Disk Erase failed with the error: Securely erasing data to prevent recovery failed. 2012-01-03 11:47:04 +0000: Preparing to erase : IBM Travelstar 2012-01-03 11:47:04 +0000: Partition Scheme: GUID Partition Table 2012-01-03 11:47:04 +0000: 1 volume will be created 2012-01-03 11:47:04 +0000: Name : IBM Travelstar 2012-01-03 11:47:04 +0000: Size : 40.01 GB 2012-01-03 11:47:04 +0000: File system : Mac OS Extended (Journaled) The drive appeared again, and I stupidly should've tried to repair the disk, but instead I ran the erase function and it displayed another error: 2012-01-03 11:47:04 +0000: Error with partition Assert: internal error or unimplemented 2012-01-03 11:47:04 +0000: Erase complete. 2012-01-03 11:47:04 +0000: 2012-01-03 12:26:27 +0000: Preparing to erase : Untitled 2012-01-03 12:26:27 +0000: Partition Scheme: GUID Partition Table 2012-01-03 12:26:27 +0000: 1 volume will be created 2012-01-03 12:26:27 +0000: Name : Untitled 2012-01-03 12:26:27 +0000: Size : 40.01 GB 2012-01-03 12:26:27 +0000: File system : Mac OS Extended (Journaled) 2012-01-03 12:26:27 +0000: Unmounting disk 2012-01-03 12:27:14 +0000: Creating the partition map 2012-01-03 12:27:14 +0000: Disk Erase failed with the error: Some information was unavailable during an internal lookup. 2012-01-03 12:27:14 +0000: Erase complete. Now the drive doesn't appear at all when I plug it in! I hope I haven't royally screwed it up, but does anyone have any idea what I can do to get my computer to detect it again so I can fix it? Really appreciate any help I can get, thanks all!