Time Capsule access via Time Machine blocked by Catalina (after clean install)

The Apple support document should be followed. That is from apple themselves.. and always worth paying attention to.

Ah I found another thread that says to erase Data one first:

https://support.apple.com/en-us/HT208496

Any other advice? More stable if I revert to the OS that originally came with the MacMini?

I would not install Catalina.. but neither would I go back too far. The backup is useless if you go back beyond what was last OS you used before the upgrade to Catalina.. so if that is 10.13 go back to that.

I think you are missing the point.

when you restore via setup assistant you restore the entire backup including OS and all your files.. the restored computer should look and behave exactly as before you upgraded to Catalina.

Hence all your photos and whatever you lost should also be there..

Go back a few days if there are issues.. as Setup Assistant will allow you to choose an exact date so restore will return the computer to exactly that configuration and file set.

Once you complete that restore and make sure everything works.. make a bootable clone of the disk.. so you never have to go through the disaster that is Time Machine ever again.

You can upgrade to Mojave.. but I would not go further with older computer. Up to you.. but Catalina I think should be reserved for new hardware.

"Canon 3100 @Martin's Mac Mini Canon 3100".

Long names with spaces are not helping.. Someone has set sharing on a computer as this seems to be very mixed up.

How exactly is the printer connected to the network? Is it set with wifi to the Time Capsule or another router in the network.

Make sure NO computer is set to share the printer. The ONLY circumstances for a shared printer from a computer is USB only where the Printer is plugged into a computer and shared to the network. If that is the case then only the one computer can have sharing set.

This is option on the Preferences /Printer setup.

I will assume you have the printer configured by wifi to the main router which is the Time Capsule.

Tell me anything wrong.. particularly if I have missed that the TC is not the main router.

I must say even my best efforts to keep a wifi connected printer alive on the network.. the brother HL-L5200DW in the screenshot was unsuccessful. It worked great for a while and then would go into a deep sleep or something and I had to power it off and on again to wake it up. I recently reverted to ethernet connection from the router and it is behaving hugely better. So if ethernet is possible.. plug it into the main router with ethernet. Also set a static IP so that the Printer is locked down. This can be done either from the printer perhaps or from the router using dhcp reservation (other terms are used but you can always lock an IP address to MAC address in the router).

You can still print by wifi even with the printer setup with ethernet.

The other possibility is to print using IPP instead of Bonjour..

This makes the fixed IP essential but it is more reliable..

I don't recall ever using Bonjour

Bonjour is automatic and default.

Don't block it because that is ESSENTIAL for Network resources to be used by the computer.. It how Apple discovers devices.

UNLESS you configure it with static IP and use IPP setup.

My recommendation is to remove every occurrence of the printer on every computer. And reboot all the computers. Actual restarts.

Then redo the Printer setup via wifi to the TC.. it does not show up because Apple is convinced their systems work perfectly. However the actual MAC address or name will show up as a client connected to the TC.

Setup the reserved IP in the TC.

Click the + box at the bottom.

For description you can just put the same printer name as you use as its network share name.

If normal setup won't work you will need to use IPP printing.. yes.. you click + box add printer down the bottom and you can manually setup a printer.

You will need to extract drivers though.. so perhaps need to use that whole horrible Canon setup.. IMHO use IPP as it is probably going to work better and the drivers should still be there from last time you setup the printer.

Printers are not designed for long life span now.. and a couple of toner or ink replacements and you can just about afford a new printer. New brother is my recommendation.. if canon are not making it easy on the Mac give them a wide berth.

I need you to make a few things clearer to me.

Tested it with cable (OK) and then wifi (not OK).

What cable.. I am guessing USB. Please make that absolutely clear.

When you test with WiFi that is very difficult if you have just configured the printer with USB which makes it a LOCAL Printer.. not a network Printer.

Don't see how to get the screen you showed for Airport Utility -- if I try add device, it says none found.

Is the TC the main router of the network.. if not this job must be done on the main router. Do you have any errors showing on the TC summary? Like double NAT which will mess things up like crazy.

Going back to your configuration of the printer wifi .. how are you doing that? Again I am unclear.

Did you use the USB connection to go into the canon actual printer setup pages and the wireless must be configured to join the wireless router.. NOT adhoc mode. It must use infrastructure mode. Is that how you did it? Or did you use WPS.. I see the main instructions from Canon say the wireless is setup by WPS.

https://ugp01.c-ij.com/ij/webmanual/Tutorial/TS3100%20series/EN/TRL/trl-3000-a.html

Printer Sharing on.

If you mean on the Mac printer setup.. No.. as soon as you turn on print sharing you totally mess up the network. Even wifi (if setup properly may not work) because it is looking for the computer and sending print jobs to the computer not the printer. Print sharing is ONLY used for a USB printer with NO WIFI CONFIGURATION. And it is only for other computers on the network to send jobs to the USB printer plugged into the computer. But if your Printer has WiFi it has an inbuilt print server and you should not send print jobs via another computer computer on the network.

Start over.. remove the printer from all the computers again. Make sure NONE have sharing turned on. Reset the printer to default.. You will need to read the manual to know how to do that.

Now only do the setup on the Mac Mini.. Until it works on the mini forget all the other computers.. none of them will work because you are not configuring the printer to the Time Capsule.. The printer will appear pretty much automatically on all the other computers via bonjour once it is part of the network.

Only do wifi setup.. although I understand if that is difficult.. use the WPS instructions .. Time Capsule has WPS but accessed only via the airport utility here. With the setup open go to Base Station and Add WPS printer.

Do not use pin method.. always use first attempt.

Trigger WPS on the printer and within a few seconds it should work. Note printer needs to be close to the TC so it has excellent wireless signal at least during the setup.

If it works properly the printer will appear as a client in the TC.

Make sure the TC is actually seeing the printer.. or use the printer test page to print out its current network configuration which will include the IP address.

That is the IP you must reserve in Airport Utility so it never changes. This can be left until last.. it is more important that you can print to it now.

You should now test. If it does not work.. open Terminal and type

ping printerIPaddress .. Where printerIPaddress is IPv4 address of the printer.. like 10.0.1.10

If ping responds then we might need to dig deeper.. but if ping does not respond you have no network connection to the printer and need to start over.. sorry. Or buy an AirPrint capable printer which are far easier to get working in my experience.

It will help me tremendously to give me your actual network setup.. with all the IP addresses.. and hopefully you can show which client is the printer and what IP it is getting. Screenshots of the entire network setup.

I went looking for Bonjour and found that iStumbler can detect it. Apparently those @Martin's MacAir etc alternative names are already set up as IPP. At least this screen shot suggests it's been setup:

I think this is wrong. and show you are configuring the Printer as ad hoc.. and not infrastructure mode. i.e. the printer is expecting clients .. whereas the printer should be a client on the router.

This is why ethernet is so much better.. if the printer has ethernet plug it into the TC.. and it will work about 200% better.