The day after I wrote about Checkmate, my daughter added a new laptop to the house. It came with Lion installed, so I went looking for my flash drive that had the Mountain Lion installer. Now, I don’t know about your internet connection, but a 4.3 GB installer file is just way too big to be downloaded every time I want to install or reinstall a system, therefore, once downloaded, OS installers are copied to a flash drive for safe keeping. One problem — the drive didn’t want to mount. Disk Utility claimed that the problem was fixed — twice. It wasn’t. So I grabbed Disk Warrior. Yes, I have multiple disk repair apps. Where Disk Utility just said that the problem was fixed, Disk Warrior actually did fix the problem.
Apple’s own Disk Utility does a lot and can fix some problems, but you really should have a second utility as backup. The big three are Alsoft’s Disk Warrior, Micromat’s TechTool Pro and Prosoft’s Drive Genius. None are cheap ($99 each), but how much data can you afford to lose? How much time can you afford to be down? I’ve owned copies of all three over the years, but I seem to go back to Disk Warrior. It’s easy to use. It does only one thing, but it does it well. Instead of repairing the drive directory file, it catalogs the drive and creates a new, clean directory file. That’s it.
TechTool Pro probably does the most, of the three, but it’s also more complicated to run and understand. I think it’s also been around the longest. A limited version was packed with a lot of Macs over the years. I’ve been told that Drive Genius is what the Apple techs have been using lately for repairs. Whichever you choose, you should have a good disk repair utility handy. You may never need it, but better to have it and not need it, than need it and not have it. Disk Warrior is available by download.