Time Machine Network Connection Failure

<<The shared volume of the shared drive is visible as a shared drive. The error occurs when I enter my password as the Registered User to gain access.>>

Could the "who can share" inside System Preferences > Sharing on the iMac have been changed by the Catalina upgrade?

Are you still listed among those able to share the drive? This question is a little tricky, because when you try to connect, the 'enter your password' box appear on the remote computer, but is asking on behalf of the computer holding the drive, and the credentials you enter must be valid on the computer holding the drive.

The WD MyBooK appears to be a simple external drive, intended for direct, not Network, connection to your MacBook via USB-3 or similar.

what cable are you trying to use?

what MacOS is running on the iMac?

Is the either shared Volume of the shared drive visible from your MacBook as a shared drive?

I, too, am experiencing this (or similar) issue since upgrading my Time Machine serving MacMini to Catalina. Previously, with all my Macs at Mojave, they all backed up to a couple of the external drives (some USB, some Firewire) connected to my MacMini, which I call server. In file sharing, all the drives are designated as being available for Time Machine. This has been working for a very long time. I upgrade this MacMini to Catalina, and all seems to be working - except that it will not allow any of the connected drives to be newly*** selected as a Time Machine Backup Disk by any of the Macs on my LAN. I say newly*** because one Mac still at Mojave continues to backup to the 'servers' drives - there has been no interruption of service, however this Mojave Mac cannot select (add) any of the other available drives. I have a MacBook Pro that I also upgraded, and in that process, the Time Machine relationship to those remote drives was disrupted, an none of the remote drives will accept a Time Machine connection.

All failures report 'The operation couldn’t be completed. (OSStatus error 13.)' I am wondering if something is wrong with the Keychain on my 'server' MacMini.

I reiterate here that my 'server' Mac is not using the SERVER app. It is just a plain old Mac, now running Catalina, and with the various drives marked, in File Sharing, as being available as Time Machine backup drives.

I made a mistake on the above post. I had said that one of my Macs was continuing to back up to the now-Catalina 'server.' That Mac backs up to 3 locally attached drives.

In reality, nothing can back up to my upgraded 'server.'

All failures report 'The operation couldn’t be completed. (OSStatus error 13.)'

I reiterate here that my 'server' Mac is not using the SERVER app. It is just a plain old Mac, now running Catalina, and with the various drives marked, in File Sharing, as being available as Time Machine backup drives.

I've read the comments offered so far, and most advise to do as I have been doing for years. What changed is the the hosting Mac was upgraded to Catalina.

What has not been heard, so far, is any mention of success by anyone who has a successful Time Machine relationship between any Mac (any OS) and a 10.15 Mac server (i.e. hosting the hard drives to which other Macs are depositing their backups.)

<<no mentions of ANY success>>

That is a feature of the Forums -- they act as a lightning-rod for those with issues.

Those whose Macs are working perfectly are happily using their computers, and not visiting here.

Hi all,

I just tried the following simple steps which seem to have solved it for me. Maybe it does for you as well:

• on the server (in my case the iMac) in the settings --> sharing tab, disable file sharing (no need to reboot or whatever)
• on the "client" side (the machine from which you want to access the external TM drive mounted on the server) force restart the finder app (via "--> Force Quit" menu
• re-activate the file sharing on the server again.

Now try to select the shared TM drive (on the client side's time machine configuration tab) again, login with the correct connections when asked and see what happens? It worked for me (as we speak the macbook is running a TM backup now 😀)

Excellent, JeeHoo, thanks for this!

I had an AppleCare senior adviser watch me use this process during our screen share earlier. I found this thread while on hold while they were looking up info they had on this kind of problem. Nothing we tried seemed to work, but your instructions worked perfectly.

got a model number or a link to the specs? I am not seeing that Wi-Fi capable model.