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Windows File Contents

Matthew Roessner
Last Modified: 2018-02-07
I have a friend who has a file on her computer that is 57 GB. It is listed as a FILENAME.XLS

The friend also has another system that has two of these ".XLS files" on them with similar file names that are 932 GB and 157 GB.

The file is definitely NOT a XLS file...  

Does anyone have any ideas on how to figure out what this file is?  My initial thought is that it might be some kind of video archive or something (based only on the file size).

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I googled "opening unknown files" and see a few suggestions. Based on the size Im imagining iso files
Matthew RoessnerSenior Systems Programmer


I attempted to change it to .iso - thinking the same thing.  That didn't get me anywhere....
Simple Geek from the '70s
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Matthew RoessnerSenior Systems Programmer


I have the files on a USB Drive already.  The current theory is that these are video archive containers that have been encrypted.  I had previously opened up the file using a hex editor (they are too big for notepad++ to handle). The first two bytes are: 5F 45  of which I couldn't find any real information on.

I did find some metadata related to the files that suggested they may have been created with either TrueCrypt or VeraCrypt - so currently attempting to download those and see if I can get to the bottom of the mystery...


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