Well, that was neat. Seems something happened with my ability to import file_id.diz for RAR files since moving to the Pi. Had to download the .deb package and build it from scratch.

FYI, anyone wondering for their RPi, you might have to as well. So as not to get saddled with the limited functionality of unrar-free, you'll most likely have to use unrar-nonfree, and then just rename the archiver command in
Mystic to unrar from rar.

Instructions for it are here:

https://raspberrypi.stackexchange.com/questions/3617/how-to-install-unrar-nonfr ee

--- Mystic BBS v1.12 A42 2018/12/27 (Raspberry Pi/32)
* Origin: throwbackbbs.com -\- meriden, ct -\- (21:1/114)

Well, that was neat. Seems something happened with my ability to import file_id.diz for RAR files since moving to the Pi. Had to download the
.deb package and build it from scratch.

There is a relatively new-ish RAR format called RAR5 so it might be that you encoutered a RAR5 format archive and the compiled rar you had didn't support it.

Since Mystic has built in archive viewing and the lightbar archive navigation, I had to write a whole new viewer for the RAR5 format in A39 or A40 or so too, which was annoying because it wasn't a slight variation to the previous formats as I was expecting it to be.

--- Mystic BBS v1.12 A42 2019/02/01 (Linux/64)
* Origin: Sector 7 (21:1/108)

On 03 Feb 2019, maskreet said the following...

FYI, anyone wondering for their RPi, you might have to as well. So as
not to get saddled with the limited functionality of unrar-free, you'll most likely have to use unrar-nonfree, and then just rename the archiver command in Mystic to unrar from rar.

Do what I did.. go grab the source code from the FreeBSD pkgsrc..
surprisingly you will find rar, unrar and lha so you dont have to use those ridiculous replacements that dont support all the options

--- Mystic BBS v1.12 A41 2018/12/27 (Linux/64)
* Origin: internal dimension + idbbs.dlinkddns.com:2019 (21:1/178)

I have noticed RAR doesn't work in A46 (which is an alpha). Is it an error in the alpha or just because I installed the alpha by itself (not upgrading anything)?
The pack command shows as rar a -inul -cl -c- -ep -o+ -y "%1"
and unpack shows as rar e -inul -cl -c- -ep -o+ -y "%1"
I get no file_id.diz info on rar. This is under Linux x64 (Ubuntu 18.04 LTS and Ubuntu 20.04 LTS and Raspbian (32 bit on the Pi).

--- Mystic BBS v1.12 A46 2020/03/29 (Linux/64)
* Origin: Mystic AlphaTest bcw142.zapto.org:2323 (21:1/145.2)

The pack command shows as rar a -inul -cl -c- -ep -o+ -y "%1"
and unpack shows as rar e -inul -cl -c- -ep -o+ -y "%1"
I get no file_id.diz info on rar. This is under Linux x64 (Ubuntu 18.04

My mistake, after looking at it some more I found rar wasn't install! No
wonder it didn't work ;) It was the newest installed versions of everything, so I had forgotten to install rar to make that work ;(

--- Mystic BBS v1.12 A46 2020/04/23 (Raspberry Pi/32)
* Origin: Mystic Pi BBS bcw142.zapto.org (21:1/145)