This hint will be useful for those who use an abnormal amount of removable devices on their personal or work computer, or those who deploy 10.5 in a multi-machine environment. When you connect such devices, Time Machine asks if you'd like to use them for backing up. You can disable that warning -- just launch Terminal, and paste this line, then press Return:defaults write com.apple.TimeMachine DoNotOfferNewDisksForBackup -bool YESTime Machine will no longer ask to use the devices you connect.[robg adds: To reverse this, you can repeat the above command with NO at the end instead of YES.]

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