Guide · Mac and Windows 11

Back up to your NAS every day, without remembering to

You bought a NAS so your work would be safe, and you still copy folders to it when you think of it. Here's how to have your work copied there every day on its own, and to hear about it when that doesn't happen.

First, keep the NAS connected

Stow™ backs up to a shared folder on the NAS that your computer is connected to. Connect it once, and have your computer connect it again every time you log in. You'll need the NAS's name (or its address), the name of the shared folder, and a NAS account that can write to it.

On a Mac

1. In Finder, choose Go > Connect to Server. Type smb:// followed by the NAS's name and the shared folder, like smb://mynas/Backups, and click Connect.
2. Sign in with your NAS account, and tick Remember this password in my keychain.
3. Open System Settings > General > Login Items & Extensions. Under Open at Login, click +, choose the shared folder (it's listed with your drives), and add it.

On Windows 11

1. In File Explorer, click This PC, then … in the bar at the top, then Map network drive.
2. Pick a letter, and under Folder type two backslashes, the NAS's name and the shared folder, like \\mynas\Backups. Tick Reconnect at sign-in and click Finish.
3. Sign in with your NAS account, and tick Remember my credentials.

Setting it up in Stow

1. Open Stow and click New sync.
2. Under From, choose your work folder. Under To, go to the shared folder on the NAS and choose (or make) a folder in it for this computer, like Mac backup.
3. Choose Only ever add. New and changed files get copied, and nothing on the NAS is ever removed, so clearing space on your computer never touches the backup.
4. Under When should it run?, choose Every day at and a time your computer is usually on. If it's asleep or the NAS isn't connected then, the run happens as soon as both are back.
5. Read the sentence at the bottom, then click Save and preview results. Stow shows every file it's about to copy before anything moves. Click to run it.
6. When Stow offers, click Start Stow when I log in. It can only run on schedule while it's running.

The first run copies everything, and over Wi-Fi that can take hours. If you can, plug the computer into the network with a cable for it. Every run after that copies only what's new or changed.

When a backup doesn't happen

If the NAS isn't connected when a run is due, Stow doesn't run and doesn't pretend it did. The sync shows Waiting for and the shared folder's name. Connect to the NAS again and the run starts on its own. If a run starts and can't finish, because the NAS is full or a folder couldn't be read, Stow says so and why.

Things worth knowing

• Edited files replace their old copy, but the old copy is kept. The older version goes into a safety net on the NAS for 30 days, and you can put it back from inside Stow.
• A changed file is copied whole. Re-export a 20 GB video and all 20 GB goes over the network again. Stow doesn't copy only the changed parts of a file.
• A NAS at home is still at home. A fire or a theft can take the NAS and the computer together. Keep a second copy somewhere else, like a drive you keep at work.
• Check that it opens. Every so often, open a few files straight from the NAS. A backup you've never opened is a guess.