Time Machine share can't be found

I’m a new user of a WD EX2 Ultra. I setup a Time Machine share, configure it in the NAS Settings, tell my Big Sur laptop to backup there, and it runs for 100 GB then stops. When I try to tell the backup to recommence, Time Machine reports “Looking for backup disk…” and never finds it. I get an error to try again when the NAS is available.

If I go into “select disk,” my Time Machine share shows up twice, once with “_smb_tcp” appended to the device name, and the user/pass prepended.

I’ve tried this several times, deleting and recreating the share. I’ve tried it logging into the NAS with my username/password, and also with the NAS configured to be public and logging in as Guest. I get the same thing every time.


a tech said that I needed to change the SMB support level on the NAS from 1-3 to 3 only unless I had a specific need to support older SMB levels.


I still have your problem on my M1 silicon Mac min under Big Sur when I do the second backup to the time machine files on the NAS under OS5

did see some notes about connecting to NAS ( a non WD nas ) using AFP and not SMB but that was not related to time machine backups

I appreciate your message but I’m not sure if you’re saying you have the same problem, or have a solution?

Does anyone have a solution? Or the same problem?

Setting SMB3 only made a slight improvement, and I am where you are. So I think this is a problem for everyone with an M1 Big Sur mac.

Is there a way to disable SMB completely?

I having an issue connecting getting my Time machine to connect after grading to WD OS5. The machine is currently indexing (21%) - is that why I cannot use my TM to connect because of the indexing? Any ideas?

I am running Catalina 10.15.7 on my machine.

While typing my first reply ( I got an e-mail there was a new Big Sur beta 1-13-2020) wanted to test that first.

I used afp://10.0.x.x to get to my WD os5 deviceand opened the timemachine -use the user name and password ( not GUEST ) and on the mac made an alias to the desktop ( like shortcuts in windows)

If you use get info you will see AFP:// xxxxx and NOT smb

SMB will not work it seems.

I made a new backup and 2 additional timemachine backups and they worked
They seemed a little slow but I was backing up 95 GB


  1. I have not tested if the backup actually will restore ( i have always use carbon copy cloner )
  2. not sure if SMB not working is Apple of WD ( or both) problem
  3. I am only testing Big Sur as that is the only OS that works on the new M1 Mac Mini.
  4. For mac/windows backups - I use Acronis and super duper and move those files to the NAS

I am testing now with Catalina ( 6 hours to finish the first backup to NAS )

using a afp://ip and not smb path to the timemachine on the nas

seems ok like the Big Sur backup reported above.