Openai/691c64c3-536c-8008-a507-c542c3a174f3

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User: how can i install macos 26.1 apps on external ssd?

how can i install macos 26.1 apps on external ssd?

Assistant: You can run apps from an external SSD on macOS 26.1, but there are some limits and a few different ways to do it.

You can run apps from an external SSD on macOS 26.1, but there are some limits and a few different ways to do it. Here’s the practical picture.

0. What macOS allows / doesn’t allow

• You cannot globally tell macOS “install all apps to the external disk”.
• Mac App Store apps and most .pkg installers will always install to the internal system volume.
• Drag-and-drop apps (most .dmg apps with a single .app bundle) can live and run happily from an external SSD.
• You can also put a full macOS installation on the external SSD and install everything there.

So the method depends on the kind of app and how far you want to go.

1. Easiest: Install drag-and-drop apps directly on the external SSD

Good for standalone apps (e.g. Firefox, LibreOffice, VLC, etc.), not from the App Store.

1. Format the external SSD (if needed) - Open Disk Utility → View → Show All Devices. - Select the SSD → Erase… - Format: APFS - Scheme: GUID Partition Map - Name it e.g. ExternalSSD.
2. Create an Applications folder on it - In Finder, open the SSD (e.g. ExternalSSD). - Create a folder called Applications.
3. Install apps there - Open the app’s .dmg or installer. - Instead of dragging the app to /Applications, drag the .app to: - ExternalSSD/Applications/ - Optionally drag the app from that folder into the Dock.
4. First launch (Gatekeeper) - First time you open it: Control-click → Open, then confirm. - After that, you can launch it normally.

✅ This saves internal SSD space, but note: the app’s settings, caches and support files still go to your internal disk in ~/Library and /Library.

2. Full solution: Install macOS 26.1 itself on the external SSD

If you want everything (apps, libraries, system) on the external SSD, use it as a separate startup disk.

A. Prepare the external SSD

1. Back up anything important on that SSD.
2. Open Disk Utility.
3. Select the external SSD device (top line, not its volume).
4. Click Erase… - Format: APFS - Scheme: GUID Partition Map - Name: e.g. macOS-External.

B. Install macOS 26.1 to the SSD

1. Open Install macOS 26.1 (from Applications or the App Store).
2. When it asks where to install, click Show All Disks and choose macOS-External.
3. Let the installation finish (the Mac will reboot a few times).

C. Boot from the external SSD

On Apple Silicon:

1. Shut down the Mac.
2. Press and hold the Power button until you see “Loading startup options”.
3. Choose macOS-External.
4. Click Continue.

Now, when you’re booted from the external system:

• All apps you install (App Store, .pkg, .dmg) will be on the external SSD’s system volume.
• Your internal macOS stays mostly untouched (good for testing or keeping it “clean”).

You can later set the default startup disk in System Settings → General → Startup Disk.

3. Advanced: Move a big non-App-Store app + use a symlink

This is only for advanced use and not recommended for App Store apps.

Example: you have a huge .app in /Applications you want to move.

1. Quit the app.
2. Move it to the external SSD, e.g.: ``bash sudo mv "/Applications/BigApp.app" "/Volumes/ExternalSSD/Applications/BigApp.app"

   3. Create a symlink in /Applications:

   bash sudo ln -s "/Volumes/ExternalSSD/Applications/BigApp.app" "/Applications/BigApp.app" ``

macOS and Launchpad will still “see” it in /Applications, but the bytes live on the SSD.

⚠️ Caveats:

• Updates or installers may break or delete the symlink.
• Code signing / Gatekeeper can sometimes be picky.
• Don’t do this for system apps or App Store apps.

4. What you can’t really move cleanly

Even if you put the .app on the SSD:

• App support data (~/Library/Application Support/...)
• Caches (~/Library/Caches/...)
• Preferences (~/Library/Preferences/...)

…will stay on your internal disk. That’s just how macOS is designed.

For Apple apps like Photos, Music, etc., the better move is:

• Keep the app internal (can’t move).
• Put the library (Photos Library, Music Library, etc.) on the external SSD and point the app there.

5. Summary: what to actually do

If you just want to free some space and wear on the internal SSD:

• Put standalone non-App-Store apps in ExternalSSD/Applications.
• Move big libraries (Photos, Music, game libraries) to the SSD using each app’s settings.
• Leave macOS itself + App Store apps on the internal, unless you’re okay booting from the external disk.

If you tell me which specific apps you care about (e.g. Xcode, Steam, big games, etc.), I can give you a per-app recipe for using the external SSD as much as possible.