external drive not seen by diskutility in mac but seen on a pc

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Joined: 19 Apr 2016, 16:36

external drive not seen by diskutility in mac but seen on a pc

#1 Post by gsiklos »

Hi all,

new user of testdisk here so please be kind. My retina macbook pro locked up the other day requiring me to power off the machine which in turn caused me to lose my partition on an external 1.5 tb drive. the drive refuses to be seen by diskutility so I am unable to use other hdd utils to try to repair it. so i moved over to my pc which is able to see the efi and main partition (only 1 partition) named downloads. but since it is a guid journaled partition the pc is unable to do anything with it. this led to testdisk . which also see's the EFI and Downloads partitions I run the quicksearch and get (SEE BELOW) it seems to stop at 99% (not sure if its still doing something!) but I also notice that the Analyse cylinder count appears to be greater than the lower value before the percentage [Analyse cylinder 182401/182400: 99%] I'm thinking that may be a problem since it only worked a few seconds to get to that point and in my experience these utilities generally take much longer to do things. so if someone can offer up some advice I will allow it to sit at this point until I either get an answer or the computer does something else.... Thanks in advance!

Code: Select all

TestDisk 7.0, Data Recovery Utility, April 2015
Christophe GRENIER <grenier@cgsecurity.org>

Disk \\.\PhysicalDrive4 - 1500 GB / 1397 GiB - CHS 182401 255 63
Analyse cylinder 182401/182400: 99%

check_FAT: Unusual media descriptor (0xf0!=0xf8)
Warning: number of heads/cylinder mismatches 16 (FAT) != 255 (HD)
Warning: number of sectors per track mismatches 32 (FAT) != 63 (HD)
  EFI System                    40     409639     409600 [EFI]
  Mac HFS                   409640 2930014983 2929605344


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Re: external drive not seen by diskutility in mac but seen on a pc

#2 Post by cgrenier »

Please post the testdisk.log file content. There is nothing in your message about the actual state of the partition table...