Data error in encrypted file 'file.7z' Wrong Password?" "File.7z

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David
2014-07-01
2014-07-02
  • David
    David
    2014-07-01

    •7-Zip version and type (32-bit / vers 7z920 )
    •Windows version and type Windows 7 Ultimate SP1 (32-bit)
    •CPU type Genuine Intel (R) CPU U7300 @ 1.30 GHz
    •RAM size 2.00 GB (1.87 GB usable)

    Created a database of 7zips and deleted originals. New to data archiving and idiotic I know. Thanksfully most archives that were burnt to disc were good. Except for two archives. They were all password protected and with default 7zip settings on compression, up to date 7zip (7z920)version. When opening the archives I was able to extract certain folders that decompressed so that there are only a couple of folders remaining that would not decompress in these archives.

    Everything else has been squared away and the removable files have been salvaged from these archives, however the remainder is sizeable, the archives created and the files inside are fairly important and mostly irreplaceable, I know, I put myself in this situation. The error that shows up upon extract or test is as the title suggests "Data error in encrypted file 'file.7z' Wrong Password?" "File.7z" has been placed instead of the file name.

    The password worked fine on the rest of the archive and from what I have gathered online it appears that these remaining files may be corrupt. Is there anything I can do to recover these files? Any advice is greatly appreciated. I apologise if this topic is covered else where.

     
  • Igor Pavlov
    Igor Pavlov
    2014-07-02

    There two possible reasons:
    1) Wrong password
    2) Corrupted data

    You can call

    7z t a.7z > test.txt
    7z l a.7z > list.txt

    if there is some "OK" file in "BAD" solid block, then it's "Corrupted data" case. In that case it's difficult to recover data.

    How to recover corrupted data.
    You must find exact place of corrupted data. Then you must find another copy of file that was compressed in that place. Create another copy of .7z arechive with same solid block including that "GOOD" copy of "bad" file with same settings. And replace "BAD" data with new "GOOD" data.