10-18-2020 08:54 AM - edited 10-18-2020 08:57 AM
I'm having this problem too with my Mac running Sierra. When I first got the mf743cdw, I was able to install the scanner driver and used it once, but since then my computer hasn't been able to find it. I can't add my printer at all through the MF Toolbox using either Bonjour or the IP address (it says the "specified scanner is not supported"), and while I can add it to the MF Scan Utility (and believe me, I've been saying "MF!" a lot during this process), it appears in Bonjour and I can add the IP address, but it says it cannoy commuicate with the scanner. Tried reinstalling and uninstalling, but nothing works. I can connect through Remote UI no problem and it shows the scanner is ready. Canon really needs to fix this problem with the drivers, it is extremely frustrating. Couple that with the fact that we're using the same unit with 3 other computers (Mac and PC), so any change in IP address or network settings makes those computers unable to find the printer.
The good news is that I did find a workaround. If I go into the Settings/Printers & Scanners, and then select the "Scan" tab there's a button to "Open Scanner" which opens Apple's built-in scanner interface... it's not great to work with, but I can indeed scan without having to reinstall anything. Also, I need to wake up the printer sometimes before it will work, but damnit, I can scan!
11-04-2020 01:47 PM
I understand you are having an issue with scanning via your wireless network with your Color imageCLASS MF743Cdw using the scanning software provided with the printer. Your MF743Cdw uses the MF Scan Utility to scan (it is not compatible with the MF Toolbox). For clarification, I have a couple of follow up questions:
1) Did you use steps similar to these instructions at this LINK to register the network scanner using the Bonjour connection?
1-1) If so, when you open the Canon MF Scan Utility from the Applications menu, is the MF743Cdw (or MF740 Series) listed in the main dialog box?
If you need immediate assistance and you're in the USA, please click http://Canon.us/ContactCF for our US-based support. If you're outside of the US, please click http://Canon.us/4xf7 for support options.
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11-08-2020 06:47 PM
Thank you for your reply. I have followed the procedure to register the scanner through the Canon MF Scan Utility, but my computer never seems to be able to find it to scan after I add it. As I said, it worked once, the first time I set it up, but the next time I tried to scan, the computer said it couldn't find the scanner, and I'm in the state I'm in now no matter how many times I readd it, or which way I add it, through Bonjour or IP address.
As I said, I have a workaround of using the built-in scanning window, so I am able to scan.