If you have access to the unencrypted files elsewhere (e.g., a different backup drive), simply create a new RAR archive without a password. Unlocking is unnecessary.
Here’s a for a portable RAR password unlocker tool — designed for ethical password recovery (e.g., lost own archives). rar password unlocker portable
This tool should be used on RAR files you own or have explicit permission to recover. Unauthorized cracking may violate laws. If you have access to the unencrypted files elsewhere (e
Download the portable version of a reputable recovery tool. (Note: Be wary of crack sites. Download from the official developer or a trusted software repository). The file will usually be in a .zip or .rar format. a different backup drive)