Sequoia Time Machine Synology NAS keeps disconnecting
I have just upgraded my 2018 Mac Mini to MacOS 15 Sequoia.
Since 2019 it has always backed up to a folder called TMFolder on a Synology DS413j.
( My partner's Mini also backs up to the same NAS, but hers is still on Sonoma. Her backups still run successfully. )
Every time Time Machine on my Mini tries to backup to the NAS now, it reports:
The backup will fail anywhere between one and five minutes after starting.
Mac mini, macOS 15.0