If you want to remove passwords from a 7z file, I recommend you use eSoftTools 7z Password Recovery Software. This software has three recovery strategies Brute Force Attack, Dictionary Attack, and Mask Attack to remove and recover lost 7z passwords. The software recovers various types of the 7z password like symbolic, alphabetic, numeric, lengthy passwords, etc. The software has a free trial edition that can recover the first three digits or letters of the password.
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