If you’re using the Apple OS X integrated Time Machine backup software, at some point you’ll likely get an error message stating: “Backup Failed. Time Machine couldn’t back up to ‘your_drive_name'” — where your_drive_name will be the backup drive you’ve assigned.
Thinking it must have just been a one-time glitch, you’ll manually run a backup, but that will result in an error as well.
You’ll then check the drive only to discover that although the backup folder exists, its contents are all gone.
You’ll panic a little, and then consider using Disk Utility to repair the disk. However, upon running Repair Disk, you’ll get a strange alert that says, “Alert. Some information was unavailable during an external lookup.”
After some hair pulling, you’ll figure the only option is to start all over again by formatting (erasing) the drive and doing a complete backup again.
However, when you attempt to erase the drive, you’ll get an error.
Problems with formatting a drive can be an indication that the partition is corrupted somehow. So, you’ll take things to the next level and attempt to partition the drive, but that will also result in an error.
At this point, assuming that the drive is defective, you’ll throw it in the trash can and purchase a new one.
The Time Machine backup program will work fine with the new drive for a while, but then you’ll get the error again stating the backup failed.
You’ll start all over again at the top of this page and get to this paragraph.
Realizing that the problem is likely not repeated failed hard drives, but something very quirky with Apple OS X, you’ll search the web to see if anyone else is having trouble with Time Machine backups. You’ll discover that Apple has dedicated an entire support page to all the things that can go wrong with Time Machine. Apparently you’re not alone.
With a mix of joy and frustration, you’ll see a link titled, “Apple Support article: Time Machine stops backing up to external disk.”
Finally your search is over.
You click the link, but it takes you to a page with an error stating, “We’re sorry. We can’t find the page you’re looking for. Please return to the Apple Support homepage.”
Assuming it’s a browser issue, you’ll switch from using Chrome to using Safari, and try visiting the support page again. However, this time, the support page won’t even load.
You’ll think to yourself, “Great. Apple’s website doesn’t even work with Apple’s browser.”
At this point you’ll want to write a blog article about the above experience, and switch to Linux.
You’ll switch to Linux.
You’ll pull your old backup drive out of the trash can, and out of curiosity, you’ll plug it into your Linux computer to find that it actually isn’t defective, and the files weren’t erased. Unfortunately, Apple’s file system permissions will be set so you won’t have permission to read the files. There’s probably a solution to that, but you’ll save that for another day.