Devices: signing out and revoking access
Every computer signed in to Sync is listed as a device, in the app under Account and in your control panel under Backup & Sync.
Signing out
Signing out on a computer stops it syncing and removes its stored credentials. Your local files stay exactly where they are — they are ordinary files in an ordinary folder — and your workspace on the server is untouched.
Revoking a device you no longer have
If a laptop is lost, sold, or belongs to someone whose access should end, revoke it from any other computer. Revoking does two things: it deletes that device's sign-in token, and it rotates the storage key for your workspace, so the revoked machine can no longer reach your files even though it still has the app installed.
Why your other computers reconnect
Because the storage key is shared by your whole workspace, rotating it briefly affects your other devices too. They still hold valid sign-ins, so they collect the new key automatically and carry on. You may see a short "reconnecting" moment; nothing is lost.
Before changing your encryption setting
You must sign out every other device first. A machine left running would keep uploading under the old setting while the workspace is being cleared. The app will offer to sign them out for you.