# Don't offer new disks for Time Machine backup

Prevent Time Machine from prompting to use newly connected storage as backup volumes.

  • Tested on macOS:
    • Catalina
  • Parameter type: bool

# Set to false (default value)

defaults write com.apple.TimeMachine DoNotOfferNewDisksForBackup -bool false
  • When a new disk is connected, system prompts to ask if you want to use it as a backup volume.

# Set to true

defaults write com.apple.TimeMachine DoNotOfferNewDisksForBackup -bool true
  • When a new disk is connected, system does not prompt to ask if you want to use it as a backup volume.

# Read current value

defaults read com.apple.TimeMachine DoNotOfferNewDisksForBackup

# Delete current value

defaults delete com.apple.TimeMachine DoNotOfferNewDisksForBackup