Scanner is recognised by "Document Scanner", starts to scan, preview appears, then gives popup with "Failed to scan. Unable to scan."
Repeated attempt to scan has Document Scanner giving "Failed to scan. Unable to connect to scanner."
EDIT: Further: Document Scanner, on opening searches for scanners.
Finds:
Brother MFC-L3750CDW
ESCL Brother MFC-L3750CDW
ESCL Brother MFC-L5755DW
I can successfully scan with "Brother MFC-L3750CDW" but neither of the ESCL scanners.
And now "Document Scanner" is asking/demanding that I reply "Yes" to popup "There is an autosaved book available. Do you want to open it?"
This is not looking like a Zorin localised problem.
I'm getting the reverse
(Brother MFC-L5755DW: working,
ESCL Brother MFC-L3750CDW: not working,
ESCL Brother MFC-L5755DW: not working),
on my LM XFCE trial machine.
Looking like (a) user error, or,
(b) software common to Zorin and LM.
(a) user error - mebbbe but installs on LM, following Brother instructions closely, of printer A drivers then printer B drivers, looked good in the terminal.
Have put rule in Firewall in LM to allow both printer static ip addresses in and out.
I see Brother says something like, "Can't use two printers with the same name with this software".
Remove your printers and then reinstall the Brother drivers. I had two show up on another distro and it was giving me weird issues as I had to keep selecting the other printer if I wanted to print or scan.
I removed both printers then reinstalled the Brother drivers and it stopped. I've had this issues on Windows before as well. It's almost like the system is trying to setup the system using whatever driver it wants, then when you install the correct driver and it creates two printers.
Why do you have 3750 if you have a 5755 machine? Did you install the wrong drivers?
Thanks DeanG.
I've got two: a 3750 upstairs and a 5755 downstairs.
Uninstalling and reinstalling sounds like a good next step. I saw uninstall instructions came from Brother with their download.
If a simple Brother-instructions uninstall-reinstall doesn't work I'll try the more complex instructions at Easy Linux Tips Project : Brother printers: how to install them
All went well but Steps 5. - 8. don't work to delete the printers from CUPS localhost:631/Printers as they get discovered and re-added immediately upon deletion.
Original problem caused by basic user error - installing incorrect packages.
Careful reinstallation has both printers printing.
But only one printer scanning correctly.
MFC-L3750CDW only shows in scanner programs as ESCL MFC-L3750CDW
Have tried reinstalling Document Scanner and installing xsane
apt --reinstall install simple-scan
But neither ESCL MFC-L3750CDW nor 'ESCL MFC-L3750CDW' will scan.
Document Scanner gets half way through the image and then error message "Failed to scan. Unable to scan." appears.
xsane shows "Error Failed to start scanner: Invalid argument"
How to get MFC-L3750CDW to show as a non-ESCL scanner?
Have removed all added-on Brother drivers on both computers.
Have also uninstalled xsane and the sane-utility drivers from Zorin.
Printing
Both Brother MFCs will print from the support in the Linux (?)kernel - without the additional drivers from Brother.
Scanning
Both Brother MFCs will do single page scans from the flatbed using from the support in the Linux (?)kernel which provides the ESCL options in Simple Scanner / Document Scanner.
Neither will do multi-page scans using the ESCL option.
Summary
There seems to be conflicts between the built-in Linux drivers and the ones provided by Brother. Removing the ones from the Brother website allows printing and very restricted scanning to occur.