‘This disk is used for Time Machine backups’


“This disk is used for Time Machine backups”
“OS X cannot be installed on ‘Macintosh HD'”

Those are the error messages I encountered today when I tried to install the new Mavericks OS X on my early 2008 MacBook Pro (it took more than 3 hours to download, but I’ve been having connectivity issues recently).

I found the fix here. It seems you have to look for and delete a folder titled “Backups.backupdb.” It didn’t show up in Finder. I dug around and found it listed with Applications, Library, System, User Guides and Users (under MacBook > Macintosh HD, as I recall) and moved it to Trash, thinking I could restore it from there if the installation still wouldn’t start.

It worked. The installation itself took an hour, maybe an hour and 15 minutes. The countdown timer hangs on “Less than a minute” for perhaps 7 minutes. Just be patient.

For the curious, Mavericks is the name of a surfing location in northern California.

8 thoughts on “‘This disk is used for Time Machine backups’

  1. Yipes. This is one of my fears and is just what has kept me from updating my iPad2 to the new IOS7 released a few weeks ago. I read advice somewhere to delay in order to let the bugs get worked out and from what I’m reading, I’m glad I did. One has to wonder if Apple’s hard-earned reputation for customer care might be slipping?

    I only updated my desktop to Lion a couple of months ago, after Quicken 7 finance software finally came up with a patch to make it compatible, so I think I’ll wait at least a few months before tackling Mavericks. I appreciate the heads up, PT. Please keep us posted on how Mavericks is working – and what difference it makes for you. Jim

    1. I wouldn’t worry about it at all. I haven’t had my backups set up properly (supposed to go to an external HD), and I think I created the problem for myself. This was a simple fix for a simple problem. My son, a developer, has updated about three different machines so far without any hiccups. And he hasn’t heard of any problems. None of Mavericks new features have been of any particular interest to me so far. What I wanted for my aging laptop was the more efficient internal functioning and resulting improved battery life, which doesn’t seem to be getting much publicity.

      I also wouldn’t judge Mavericks by the iPad OS. Two different creatures.

        1. I’m feeling cocky since I found the solution and fixed it myself (without The Son’s help). If I can do it, anyone can do it.

          Now if I could just get my backups to run properly …. 🙂

    1. Well, I was downloading within the first 24 hours it was available (along with most other Mac owners in the country). And my wifi connection seems pretty slow most of the time. And it was big — 5.29 GB. I can deal with the waiting as long as I know things are moving along properly. Hey, it was free. Hard to complain about that.

... and that's my two cents