Dear Lifehacker, I was recently performing maintenance cleaning on MacBook Pro [late 2011, 17" 128GB SSD, 8GB RAM] , and there is a file on the SSD that is 27GB and says "backup". I can't for the life of me find where the heck that file is, or WHAT it is, or how to get rid of it! Any ideas? Thanks, Clogged Mac
Dear Clogged Mac,
Our assumption is that you're using Time Machine as your backup system. One of the neat features of the more recent iterations of Time Machine is that they use some of your spare disk capacity to keep backing up your files even though you might not be connected to the external storage you use for backups.
If you click on the Apple icon on the menu bar and choose "About this Mac" click on the Storage tab and you'll see what's using your disk space. Backups will be on the list.
There's no need to do anything about it as the operating system will manage its size and reduce it as the amount of space it uses will be automatically reduced as disk space becomes more limited.
If you want to force a deletion, you can set it to zero and turn off local backups by using the terminal command
sudo tmutil disablelocal
Of course, that will mean you won't have a local backup of any files you accidentally delete or edit.
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