This is a QNAP not a Syno forum..copy pasted too fast ?
I’ve been having issues backing up from my Macs that are running 26.2, but the ones running 26.1 work just fine. It seems like apple tightened down some of the settings so that it now rejects network shares that it cannot verify when it used to just accept them. It seems the solution is to update SMB to v4.22.7. I just updated my NAS tonight and it is still running 4.15.004.
Note that my backups do not contain special characters in their names, so that issue isn’t the one at play for me.
The details I found were in this apple forum thread:
There’s a known regression where Time Machine capability advertisement over SMB breaks, so macOS now flags the share as unsupported instead of silently accepting it. Apple isn’t detecting fruit time machine anymore, not because your config is wrong, but because the SMB server isn’t responding exactly how Tahoe expects.
So QNAP, can we get an update to SMB so that Time Machine works again? It sounds like this issue was actually fixed in SMB months ago…
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