I had some files on an old thumb-drive, and recently I was going through and discovered that all/most of the files were no longer readable by any of my macs. I seam to remember having similar problems like this while back, and finding an apparent link to my choice of format, so I ran diskutil list in terminal:
/dev/disk3 (external, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *134.2 GB disk3
1: EFI EFI 209.7 MB disk3s1
2: Apple_HFS my-old-files 133.9 GB disk3s2
And I tried ls -l
total 3858320
-rw-r--r--@ 1 kipbits staff 3430100 Nov 21 2016 2015-12-24.pdf
drwxr-xr-x 8 kipbits staff 272 Sep 26 2016 2016-sep-14-files
-rw-r--r-- 1 kipbits staff 25642888 May 18 2015 myold.mp4
-rw-r--r--@ 1 kipbits staff 884 Jul 31 20:20 someold.txt
-rw-r--r--@ 1 kipbits staff 1320157184 Sep 21 2016 someold.iso
drwxr-xr-x 4 kipbits staff 136 Sep 27 16:23 anotherdir
-rw-r--r--@ 1 kipbits staff 626214959 Nov 5 2016 someold.mp4
drwxr-xr-x 14 kipbits staff 476 Nov 2 2016 sept2016files
I think this looks normal?
The problem is, I'm not able to open any of my files. I get the following errors:
pdf:
**The file “some-old.pdf” could not be opened.**
It may be damaged or use a file format that Preview doesn’t recognize.
txt: 800 byte files are blank
rtf:
**The document “some-old.rtf” could not be opened.**
mp4:
**QuickTime Player can't open "some-old.mp4".**
To see if additional software is available that will enable QuickTime Player to open the movie, click Tell Me More.
dmg, iso: will mount but did not test further
pkg:
**The operation couldn’t be completed. (com.apple.installer.pagecontroller error -1.)**
Couldn't open "some-old.pkg"
I found a thread on apple saying "The partition map type doesn't really make any difference for non bootable volumes", although i don't get any of these problems when using Master Boot Record & ExFAT.
None of the files are more than a couple years old, so i don't think there should be any compatibility issues, and none of the files were corrupted when I copied them to the drive. I have had this same problem with other drives, and they were perfectly usable after reformatting, although this involved erasing files.
My question is: Is there a way to recover my files? The file-sizes still display that the files are there. Is there a way to save these files and make them readable?
...Also, if it makes any difference, I am using El Capitan(for dev purposes)
Update------------------------------------------------------------------------------------------------(04/Oct/2017)
I did a hexdump for some of the files in question. my output was something like this:
0000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0000370 00 00 00 00
0000374
what does this mean? do you think a recovery app could even help me here?
here are some threads that are perhaps related:
...Also could this possibly be related to SIP? I first noticed this problem around when i first upgraded to El Capitan.
Or perhaps there is something else going on? I have recently been experimenting with windows and various forms of linux, and have been moving files around with thumb drives. Perhaps I plugged one in to the wrong computer and corrupted all the files?
Whatever the cause, I'm wondering if the files might still be recoverable? Is hexdump a good way to diagnose recoverability? Would buying a recover app just be a waste of $100?
