If you’ve just purchased yourself a new slim Seagate external hard drive to use as a back up for your mac and you get the following error: seagate The backup disk is not in Mac OS Extended (Journaled) format, which is required.

Don’t panic! It’s a very simple fix and only takes a few moments.

  1. Press Command & Space rapidly in unison to bring up Spotlight Search
  2. Type: Disk Utility
  3. Choose the Seagate drive and click eraseHow to format your Seagate drive in Mac OS 10.11
  4. This will pop up a window to rename the drive. Do so. Name it whatever you would like to see when it pops up in Finder
  5. Ensure you have chosen the following settings for the next two drop-downs:
    Format: OS X Extended (Journaled)
    Scheme: GUID Partition Map
    How to format your Seagate drive in Mac OS 10.11
  6. Click “Erase”. This will create a new instance of this drive with the correct formatting to allow the Seagate drive to be used with Time Machine
  7. Go to System Preferences
  8. Press Command & Space rapidly in unison to bring up Spotlight Search
  9. Type in System Preferences and hit return (enter)
  10. Click on “Time Machine”
  11. Click “Add or Remove Backup Disk”
  12. Remove the original Seagate disk you installed there
  13. Add the newly named Seagate backup disk

You’re all set!

 

Citations: http://knowledge.seagate.com/pkb_ArticleView?id=kA030000000iKvn