How to Troubleshoot external drives

1 Check your screens

We’ve found that when we wake our Mac from sleep, macOS sometimes moves all our drives to the external display or doesn’t re–initialize the USB ports. Unplugging and reconnecting the USB cable(s) will fix the latter.

2 Look at locations

The Finder sidebar includes a section headed Locations, which you may have to scroll down to see: here you’ll see any connected storage devices and your main Mac drive. If your drive is visible, you can click to see its contents.

3 Check your desktop

If your drive is appearing in Locations but not on your desktop, go into Finder’s Preferences and look under the General tab. If the checkbox for a particular kind of drive isn’t checked, it won’t appear on your desktop.

> Why can’t Spotlight or Siri find my file?

Spotlight and Siri don’t necessarily search for every kind of file: if you take a look in System Preferences > Spotlight > Search Results you’ll see a big list of categories. If a category isn’t checked, it won’t be included in search results. You can also exclude specific folders in the Privacy tab.

> Why aren’t my files in Time Machine?

Assuming your backup drive has enough space for full backups, are the missing files in a folder that you’ve excluded from your Time Machine backups? Follow the steps on the right to check; if a folder shouldn’t be in the list you can remove it by selecting the folder and then clicking the "–" button.

> Where’s my file gone? How do I get it back?

Check the Bin, search for its file name in Spotlight or use Recents in the Finder sidebar (or the Recents bit of the app’s File menu). If you’ve accidentally overwritten it you can use File > Revert To or Time Machine to go back in time to find and recover a previous save.

> Why does Time Machine keep timing out?

Antivirus software is a known offender here: if you can, exclude your backup disc from its scanning. Time Machine also goes slow when your system is under heavy load or is running out of battery, and the “preparing” stage can take longer if the previous backup was interrupted.

> Why isn’t my external drive showing up in Finder?

If it’s a Mac-formatted drive that previously worked you’re not alone: this happens to us frequently, especially when we wake our laptops from sleep. The tutorial below will help you diagnose your missing drive.