If you also want to Extract a 7z file without a password then you can use eSoftTools 7Z Password Recovery Software which does not harm your 7z file. This software has three methods namely Brute Force Attack, Mask Attack, and Dictionary Attack which help a lot in recovering 7zip files. It also supports recovery of all types of 7zip. A free demo is also provided to all users using which you can recover the first three characters of the 7zip file.

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