Sorry Richjohn, please pardon my technical ineptitude when it comes to the apple discussion group. Presumably you are asking what my issue was, and what fixed it? The Issue: After installing BigSur my Lexmark CX310 failed to print, generating a filter fail error. The simple fix, suggested by Daniel Marr, was to RESET the Mac printing system, as follows: 1. On your Mac, choose Apple menu > System Preferences, then click Printers & Scanners.
2. Press and hold the Control key as you click in the list at the left, then choose “Reset printing system” from the menu that appears.
3. After you reset the printing system, the list of printers in Printers & Scanners preferences is empty.
4. Re-add any printers.
So that's it. Worked like a charm.