MacBook Pro (Mid 2012, MacOS Sierra 10.12.3) I got a new 1TB external hard USB drive for the MacBook Pro backups. With this new drive, the Time Machine backups are grayed. How can I start afresh to use this new drive by deleting the old grayed backups? The backup links should be in the Mac Book since the original external USB drive does not exist anymore. Some tutorials I found on YouTube skipped important steps and were too quick to explain to the viewer. Thanks in advance.