Full Disk Access is on but the app says it isn't

If System Settings shows Storage Studio switched on under Full Disk Access but Storage Studio says it isn't granted, macOS has stopped honouring the permission — you did grant it. macOS ties the permission to the exact copy of the app, so an update, a repair or a second copy can quietly break the link. Switching it off and on again, then clicking Re-check, fixes it in most cases.

What you might see

• A prompt headed Your Mac has stopped honouring this permission: "You already gave Storage Studio Full Disk Access, and your Mac isn't accepting it any more — that happens when the app is updated or repaired. Switching it off and back on in the list below restores it."
• A notice: Full Disk Access has stopped working.
• Storage Studio was blocked from some of your files — when macOS refused access in the middle of a job. Whatever couldn't be read was left out, not counted as empty.
• In Settings → Permissions, the Full Disk Access row shows Not granted or Unknown.

Likely causes

• Storage Studio was updated or repaired. The new copy isn't the one macOS gave permission to.
• There's more than one copy of Storage Studio — for example one in Applications and one left in Downloads or on a disk image — and the switch you turned on belongs to the other copy.
• Storage Studio hasn't checked again yet. It checks when it starts, when you open it from the menu bar, while the permission prompt is on screen, and when something is refused. Otherwise, Re-check makes it look straight away.

%% caption: Getting Storage Studio to see Full Disk Access again
flowchart TD
  A[Switch is on but Storage Studio says not granted] --> B[Open Settings, then Permissions]
  B --> C[Click Open Settings]
  C --> D[Switch Storage Studio off, then on again]
  D --> E[Back in Storage Studio click Re-check]
  E --> F{Granted?}
  F -->|Yes| G[Done]
  F -->|No| H[Remove Storage Studio from the list and add the copy in Applications]
  H --> I[Delete any other copies and restart Storage Studio]

How to fix it

1. In Storage Studio open Settings…, then Permissions, and click Open Settings on the Full Disk Access row. (The prompt's Open System Settings button does the same.)
2. In the list, switch Storage Studio off, then on again.
3. Come back to Storage Studio. If the permission prompt is open, it notices on its own — "We'll detect it automatically — no relaunch needed." Otherwise click Re-check.
4. Still not granted? Remove Storage Studio from the Full Disk Access list with the minus button, then add it back with the plus button, choosing the copy in your Applications folder.
5. Make sure there's only one copy. Delete any others (in Downloads, on your desktop, or on a disk image you still have open). In Settings → Advanced, the Permissions section has Show Storage Studio in Finder, so you can see which copy is running.
6. Restart Storage Studio from the menu bar icon's right-click menu, then check again.

Why it matters

Without Full Disk Access, macOS keeps Storage Studio out of protected places such as Documents, Desktop, Downloads and your Library. Storage Studio then leaves those places out of scans and rules rather than guessing — see My rules don't move anything from Documents or Desktop.

See also: Why Storage Studio asks for Full Disk Access · The permissions Storage Studio asks for · Full Disk Access · Something's not working: start here