Cannot open encrypted dmg folder; Message says "The disk you attached was not readable by this computer"
I created an encrypted disk image folder with very important and sensitive documents, photos, and videos that I could open just fine with my password just a few years ago. For over a year, whenever I click on this .dmg file and enter my password, I get a message that tells me "The disk you attached was not readable by this computer" and only gives me three options: eject, ignore, or initialize.
I've seen other posts with people describing similar issues and I've tried a number of things: including using Disk Utility's First Aid on the .dmg file, copying the dmg file to other drives and trying to open it that way, as well as several other steps, but nothing has produced the result of me being able to open this dmg. I'm sure I have the right password.
Here's some info on my device: MacBook Pro 13" 2017 w/ 4 Thunderbolt 3 ports, 3.1 GHz Dual-Core Intel Core 5 processor; Memory: 8 GB 2133 MHz; macOS Monterey 12.6.7). The .dmg file is on a Sandisk 1 TB SSD external drive, but it is also on other drives that also no longer open on my MacBook Pro. Thanks ahead of time for any help and tips.
MacBook Pro (2017 – 2020)
