It worked on the day you set it up. Then the NAS rebooted for an update, or the PC went to sleep, or the router handed the PC a new address - and the folder was empty. None of these are mysteries. Set up for all three once, and the mount simply stays.
A mount is a live relationship between two machines: it survives only while both addresses stay put and both machines stay awake. That is not a flaw - it is the definition of mounting instead of copying. The good news is that all three breakers are boring and predictable, and Synology plus your router give you a setting for each one.
👆 Four small settings between a mount that lasts a year and one that dies quietly in the first month.
This is Synology's own checkbox in the mount wizard, and it decides whether the mount is permanent or a one-session favour. Without it, a NAS reboot - including the automatic kind after a DSM update - removes the mount silently. If your existing mount was created without the tick, there is no edit button: unmount it (File Station → Tools → Unmount) and create it again with the box ticked. Two minutes, once.
The mount stores the address you typed. Synology states the consequence plainly: if you set a remote folder up by IP and the IP changes, you must unmount it and set it up again - the mount cannot follow the PC to a new address. Prevent the change instead:
192.168.1.50, for the PC's network cardA reservation is the safe way to fix an address: the router always offers the PC the same one, and you never hand-type network settings on the PC itself. Do the same for the NAS while you are in there.
A sleeping or shut-down PC serves nothing - the mounted folder on the NAS will look empty or throw errors, and any backup job reading it fails for the same honest reason. If jobs depend on the mount overnight, set the PC's sleep to Never while plugged in (Settings → System → Power), or wake the PC before the job runs. Wake on LAN can help on PCs whose network card supports waking, but the simple, reliable answer is: the serving PC stays awake while it is serving.
If the network dropped and the mount shows as disconnected rather than gone:
Windows drive letters have the mirror behaviour: a red X after the NAS slept looks alarming, but opening the drive makes Windows reconnect on access. Reach for Reconnect before you reach for deleting and recreating anything.
Once a month: reboot the NAS, wait for it to come back, open the mounted folder, and copy one small file across. That is the whole test. Mounts fail silently - nothing phones you when one dies - and the failure is usually discovered on the worst possible day, when a restore or a backup is actually needed. A mount that passes the monthly reboot test is one you can build jobs on.
Watch the video once for the setup - this page is the checklist that keeps that setup alive month after month.
▶️ Watch Full VideoOne of two things: the mount was created without Mount automatically on startup, so the reboot removed it - or the PC was asleep or off at that moment, so there was nothing to show. Check the PC is awake, confirm the share still opens from Windows, then re-mount with the startup box ticked.
Not as part of the mount itself - serving files is the PC's job, and a PC that is off cannot serve. Some setups use Wake on LAN from another always-on device to wake the PC first, but the dependable pattern is simpler: keep the serving PC awake during the hours its folders are needed.
No - DSM does not let you edit the stored path of an existing remote folder mount. Unmount it and create it again with the new address, ticking Mount automatically on startup. Then reserve the address in the router so you never have to do it twice.