External hard drive's files inaccessible..?

jozefpawel

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Jul 30, 2015
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So, a while back my PC's hard drive went caput, and I had its data recovered and put on a cheap WD My Passport drive by an IT guy. When I got the hard drive and connected it to any computer, though, its files wouldn't open They were the correct sizes and extensions, but the computer-- any computer --would not recognize them. Pictures would just open to the generic Windows icon for photos, and text files were blank.

I contacted the IT guy and he said he had no problems with the files-- they were all healthy --and managed to send my my documents/music/pictures; indeed, they were all in tact. So the originating files were all fine, it just seems like something happened when he moved them from his server to the external drive.

Flash forward a couple months, and it turns out I need some files that weren't in my documents. I have the original batch on the external drive-- still inaccessible --and was wondering if anyone on here had any idea as to what might have happened to them. Are they fragmented? Formatted incorrectly? Encrypted somehow? Corrupted? Compressed? Any help whatsoever would be appreciated.
 

puttynene

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Oct 29, 2014
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i guess what has happened here is those files were fragmented and once they were deleted, the cluster chain was removed as well. And when these files were recovered, what happened was, they did was to look at the starting location (which is still present) and the size of the file (which is also still present) and simply copied that many clusters in a row from the start. If works fine if the files are stored in a single block, but if they are fragmented then blocks spread out and one has no understanding to know where/ which ones to use.that's why most of the corrupted recovered files will have at least one cluster's worth of correct data, but then contain whatever happened to be in the subsequent clusters that used to belong to other files.

Sata-recovery programs do is to search the disk and check each cluster to see if they contain the signature of various different file types. If a cluster contains a signature, then it copies that cluster.

I guess speak to the IT guy again