After upgrading to MacOS High Sierra: The selected network backup disk does not support the required capabilities

I just wanted to add that, for me, the key part of the solution was not just to update user read/write permissions to the TM backup device as @AndreiD suggested, but then to right click on the shared folder and select "Apply Permissions to Enclosed Items".

I agree that this is one of the worst UI decisions I've seen from Apple (or anyone, really) in a long time.

I seem to have fixed the problem on our machine, I hope. I ran into this problem yesterday after I updated my wife's laptop (with a MacSales SSD) to High Sierra. The TM backup over the network to the external disk on my iMac failed with that error message. Before I tried the steps outlined by AndreiD I disconnected her connections to the shared drive and double-checked that sharing was being done by SMB, which it was. I checked and her SSD did get converted to APFS. I then rebooted her machine in Safe Mode (holding down the shift key). After it fully booted I shut it down and restarted it again normally. This time TM worked correctly, although it said that it needed to back up 27 GB to the drive, taking over 7 hours. It didn't actually take that much space, more like 15-20 GB, but that does seem large. Guess it was due to the OS upgrade number of changed files.

My external shared drive/TM destination worked fine after High Sierra upgrade once I stopped/removed the volume share and then re-added it plainly: in System Preferences > Sharing > with File Sharing [active],

using "+" under "Shared Folders:" list, added 'theVolume' then

control-clicked 'theVolume' name/shared-drive icon in list for > Advanced Options

in dialog I deselected 'Allow guest users' and selected 'Only allow SMB encrypted connections' and 'Share as a Time machine backup destination' [no limit set in my instance], then "OK"

n.b., I left untouched the new share's DEFAULT "Users:" list,

'Systems Administrator' & 'Administrators' with 'Read & Write' and 'Everyone' with 'Read Only' privileges.

Curiously: in the listing the shared-drive icon became a shared-folder icon.

I started the local machine backup from menubar and it worked fine -- even though the 'tmutil backupdestination' ID for the local machine destination had changed, it apparently inherited/associated the correct sparsebundle/backup image.

On a local subnet Mac I selected the newly 'shared-folder' as an 'other destination' and it connected the correct sparsebundle and has been backing up without error or re-duplication [I did have to re-enter credentials as expected].

I have a virtually identical set up using a mac mini as a server with a raid box attached to it over usb-c to take the network's time machine back ups. All machines are updated to high sierra but not all have this problem. Sometimes the backup works, sometimes I get the same error message as you. Sometimes a restart makes it work just once, other times it works for longer (I have on the present cycle had two days of regular backups) can't see a pattern or logic. I wish they had left time machine in the server app! This definitely seems like an issue either with either High Sierra or the new file system

I have solved this problem by creating a new Timemachine.sparsebundle with 128-bits AES-coding, Mac OS journaled.

Moved the sparsebundle to the network drive, activated it and in the terminal app entered:

"

sudo tmutil setdestination /Volumes/TimeMachine

After this my Time machine was working again. Don't know how to code existing backups <:(

Did you verify that it works on subsequent backups?

Doing that (and/or converting the drive to AFPS) resulted in the same: inheriting/the first backup runs fine, but the subsequent incremental backups fail again with the “does not support the required capabilities” error message. I assume now that “required capabilities” have something to do with figuring out incremental backups.

I run backups for all of the Macs in my home (we have quite a few) to a Mac Mini connected to two Drobo USB3 arrays. This problem has been driving me crazy for a while, until I tried upgrading one of the USB volumes to APFS.

Disclaimer:

If you are not comfortable performing these steps, DO NOT DO IT. You can lose data easily by messing around in "diskutil" command line... I cannot be responsible for your individual configuration. This is what worked for me:

1. Delete the share point that was in use by Server for Time Machine

2. You may have to force unmount the drive (Terminal -> diskutil unmountDrive /dev/disk2s2 (or whatever your volume happens to be)
3. Re-mount the drive and using Disk Utility UI, select the volume and from the Edit menu, select Convert to APFS

This is very unlike Apple to make such enormous changes and not publish documentation (or easy to find documentation). In this case, APFS was the only thing that worked for me.

Hi Chris,

Did not try your solution yet to the same problems I have but I noticed a very strange issue. When I connect my Macbook Time machine to my Mac mini with the shared folder, it wants me to log in. Whatever I type in, the response is the same! So no wrong password animation, just "the selected network backup ......"

Looks like there are more strange bugs in High Sierra with passwords i guess. At work we have an issue where the finder crashes when accessing a shared folder on a Windows server through smb3. Apple has so far no solution yet.

Prepare for APFS in macOS High Sierra - Apple Support