Modern versions of macOS require that applications be granted the "Full Disk Access" privilege to enable or disable automatic backups. If you use the Disable Time Machine backups while connected feature without granting Viscosity this privilege, then you may see the alert below.

Granting Full Disk Access

To resolve the issue, click the Open System Settings button to be automatically taken to the necessary section in System Settings. You can also get to this section manually by going to the Apple menu, selecting System Settings, selecting the Privacy & Security section to the left, and clicking on the Full Disk Access section to the right. Scroll through the list on the right until you find Viscosity.app. Toggle the option next to it, close the window, and you're done.

If you don't see Viscosity listed, you may need to restart your computer, and then connect a VPN connection again so Viscosity can attempt to disable Time Machine again.

Troubleshooting Full Disk Access

In rare instances granting Full Disk Access to Viscosity may not appear to work. This is not a bug with Viscosity, but rather points to a problem with the Transparency Consent and Control (TCC) system on the local computer. If you have granted Viscosity Full Disk Access but are still receiving the message from Viscosity indicating it was blocked from enabling/disabling Time Machine, then please try the following suggestions:

1. After granting Viscosity Full Disk Access, try restarting your computer. In some instances, TCC may not automatically reflect the changed permissions, which a restart will usually resolve.
2. Make sure Viscosity is installed in the global Applications folder. There have been mixed reports about applications running from outside the Applications folder not being granted Full Disk Access permissions. If you need to move Viscosity into the Applications folder, remove and re-add the Full Disk Access permissions.
3. Check for antivirus, enterprise management, and endpoint security software. There have been reports that such software can interfere with TCC. In particular "ESET Endpoint Antivirus" has caused known issues in the past. Try temporarily uninstalling any such software, remove and re-add Full Disk Access permissions, and see if the issue persists.
4. If you have multiple copies of Viscosity installed, make sure Full Disk Access has been granted to the correct copy. Please see the Troubleshooting Viscosity Problems (Mac) article for tips on how to check for extra copies of Viscosity (including hidden copies that could be left over from a failed update).
5. Make sure the Viscosity application hasn't been damaged or modified. This will break its code signature, causing Full Disk Access permissions to not be applied. If in doubt, we recommend downloading the latest version of Viscosity, and then copying the Viscosity application into the Applications folder by clicking and dragging it.
6. Try uninstalling and reinstalling Viscosity and its helper tool. Please see the Uninstalling Viscosity (Mac) and Installing Viscosity (Mac) articles for instructions.
7. Open the Terminal and enter the command sudo tccutil reset All. Please note that this command will reset all previously granted privacy permissions and settings (not just those for Viscosity). Restart your computer, and then attempt to grant Viscosity Full Disk Access again.

If after these steps Full Disk Access permissions are still not correctly applying, it likely points to a more serious issue with TCC on the local computer. We recommend getting in touch with your system administrator or Apple in this case.