--- title: "Shared Folders: keeping a folder the same on two Macs" url: https://storagestudio.us/wiki/shared-folders-between-macs category: "Cloud accounts" tags: ["bridge", "collab sync", "two-way sync", "devices"] summary: "Collab Sync keeps one folder mirrored between two paired Macs running Storage Studio, directly between the Macs and not through a cloud service. The newer version of a file wins, the other is kept, and deletes are only passed on if you ask." updated: 2026-10-01T05:32:12.000Z --- # Shared Folders: keeping a folder the same on two Macs Collab Sync keeps one folder mirrored between two paired Macs running Storage Studio, directly between the Macs and not through a cloud service. The newer version of a file wins, the other is kept, and deletes are only passed on if you ask. Collab Sync keeps a folder the same on two Macs that both run Storage Studio and are paired with [Bridge](https://storagestudio.us/wiki/bridge-devices). A change on one Mac is copied to the other, directly between the two Macs rather than through a cloud service. If both Macs change the same file, the newer version is kept and the other is saved, so nothing is lost. ## Two ways to share a folder between Macs - **Share a folder** — on a paired Mac's card in the **Devices** tab, **Folders you share with *Mac*** › **Add folder…** lets the other Mac open that folder from its Finder. New shares are read-only; switch on **Write** to let the other Mac change the files. The files stay on your Mac. - **Collab Sync** — keeps a full copy of the folder on **both** Macs and keeps them matching. Use this when both Macs need the files even while they're apart. ## Setting up a synced folder In the **Collab Sync** window, click **Add a synced folder**. It's only available once another Mac running Storage Studio is paired. 1. **Sync with** — choose the other Mac. 2. **This Mac's folder** — click **Choose…** and pick the folder. 3. **Direction** — **Both ways**, **This Mac → other Mac**, or **Other Mac → this Mac**. 4. Click **Review**. Storage Studio checks the folder and shows **This is what will mirror**: its size, how many files, and how many hidden or cache items will be skipped. 5. Click **Send request**. The pair shows **Waiting for *Mac* to accept…** and nothing syncs yet. On the other Mac, the request shows as ***Mac* wants to sync a folder with you**. Its owner clicks **Review**, chooses where to keep the folder with **Choose…**, and clicks **Grant** — or **Decline**. They can narrow the direction you asked for, but never widen it. ```mermaid %% caption: How a synced folder is set up, and what happens when both Macs edit the same file flowchart TD A[Add a synced folder, then Review] --> B{Is the folder allowed?} B -->|No| C[Blocked with a reason, pick another folder] B -->|Yes| D[Send request] D --> E[The other Mac chooses where to keep it, then Grant] E --> F[Changes copy across between the two Macs] F --> G{Same file changed on both Macs?} G -->|No| F G -->|Yes| H[Newer version kept, the other saved for Review] ``` *Flowchart — How a synced folder is set up, and what happens when both Macs edit the same file. Outline:* - Add a synced folder, then Review - leads to Is the folder allowed? - Is the folder allowed? - No: leads to Blocked with a reason, pick another folder - Yes: leads to Send request - Send request - leads to The other Mac chooses where to keep it, then Grant - The other Mac chooses where to keep it, then Grant - leads to Changes copy across between the two Macs - Changes copy across between the two Macs - leads to Same file changed on both Macs? - Same file changed on both Macs? - No: leads to Changes copy across between the two Macs - Yes: leads to Newer version kept, the other saved for Review ## Which folders can be synced To keep you safe, some folders are refused outright, with the reason shown in red: - your whole Home folder, or a disk or system folder — **Choose a folder a few levels deep — not a disk or system root.** - top-level folders such as Documents, Desktop or Downloads themselves — pick a folder inside them instead; - a folder Storage Studio itself manages for moves to your external drive. A folder over 25 GB or 50,000 files needs a second tick: **Sync it anyway.** Inside a synced folder, hidden files, Finder's own files, caches and half-written temporary files are skipped. A file is also left until it's closed, and until it hasn't changed for 10 seconds, so half-saved work isn't copied. ## Deletes are your choice In **Both ways** mode, deleting a file on one Mac does **not** delete it on the other. In a one-way sync you can switch on **Also remove files on the other Mac when I delete them here**. It's off by default, and even then the file goes to the other Mac's Trash, so it can be recovered. If a very large number of deletes arrive at once, Storage Studio skips them and tells you, rather than emptying the folder. ## When both Macs edit the same file You'll see **A file changed on both Macs** (or how many). The newer version was kept automatically. Click **Review** to see each one: **Restore** puts the other version back and syncs it, **Reveal** shows it in Finder, and **Dismiss** keeps the newer one. If the other Mac has a file open right now, the pair shows **In use by *Mac*** as a warning — you can still edit. ## Pausing and removing **Pause** and **Resume** stop and restart one synced folder. The remove button stops syncing it; files already synced are left in place on both Macs. See also: [Bridge: connecting another device](https://storagestudio.us/wiki/bridge-devices) · [Two-way sync](https://storagestudio.us/wiki/glossary-two-way-sync) · [Copy, Move, Sync or Two-way sync](https://storagestudio.us/wiki/copy-move-sync-or-two-way-sync) · [The Trash and the space it holds](https://storagestudio.us/wiki/the-trash) ## What links here - [Bridge: connecting another device](https://storagestudio.us/wiki/bridge-devices) - [How Storage Studio protects your settings on this Mac](https://storagestudio.us/wiki/your-settings-are-encrypted) - [Two devices won't connect with Bridge](https://storagestudio.us/wiki/bridge-devices-cant-connect) - [Where to start: pick your goal](https://storagestudio.us/wiki/where-to-start)