File Sharing Stopped Working
I have been accessing files stored on an external USB hard drive connected to my MacMini (2011, High Sierra; version unknown; "About this Mac" doesn't seem to work) from my Macbook Pro (2022, MacOS 12.6 Monterey) for years, up until recently - now getting "connection failed" message.
• I can connect to the MacMini through TeamViewer no problem
• I can access files in the other direction, opening files on the MacBook with the MacMini
Potentially related developments that could be connected; but unlikely. I'd bet on a recent OS update, but worth mentioning because I'm stumped:
1) I use a 3rd party app (Jettison) used to protect volumes from the dreaded "disc not properly ejected" issue. It also manages network volumes, but can get wonky with OS updates.
2) When I choose "remount all disks", a drive titled "Update" appears (contents in screenshot). I have no idea what this is or where it came from.
3) I tried to create a bootable recovery drive for Monterey on thumb drive. I don't know if it worked, but I mounted it recently to see what was on it, possibly around the time this started
Any ideas appreciated.
MacBook Pro 13″, macOS 12.6
> System Settings, then click Users & Groups 
in the sidebar. (You may need to scroll down.)