Could someone suggest the best 7z password recovery software for Windows?

If you're comfortable with the command line and have a Linux environment set up, rarcrack is a legitimate option to consider. Just be prepared for a potentially slow process, especially if you don't have a good idea of what the password might be. And as a wise blogger suggested, it's a good idea to test it on a file you know the password to first, just to make sure everything's working before you try it on the real thing.

Here's what rarcrack is all about:

It's for Linux: This is the first major hurdle. rarcrack is a command-line tool built for Linux systems. You can't just download and run it directly on Windows. You'd need to use something like Windows Subsystem for Linux (WSL) or a virtual machine to run it. This is because it depends on Linux libraries like libxml2 to work.

It's a Brute-Forcer: As a 7z password recovery software. It works by trying every possible combination of characters until it finds the right one. You can set parameters like how many threads to use (to speed it up with multiple CPU cores) or narrow down the character set if you have a clue about the password. However, a key point from the documentation is that it actually runs the 7z program repeatedly for each password guess, which is, quote, "really slow".

It Supports 7z: While it was originally designed for RAR files, it definitely works for 7z files too. You can let it auto-detect the archive type or specify it with the --type 7z option to make sure it doesn't waste time.

It's a Free 7z password recovery software, Open-Source Tool: The good news is that it's completely free to use. You can find its source code and package it for different Linux distributions, but keep in mind that its official homepage is no longer active, so you might have to hunt for the source code or packages.