- Holding copies of files in case a device were to crash or get lost
- Storing files because a device is low on space
- Providing quick access to files when the original device is not portable
- Transferring large files that can be rejected by mail servers
How to Get External USB Drives to Work With Macs
Typically when an external USB drive is connected to a computer it is identified and usable within a minute. Unfortunately, when connecting to a Mac, the USB device may have only limited access. Checking the permissions of the drive will show read & write permissions, yet trying to write to the device fails. This happens because of a permissions issue that is most likely caused by the device being accessed using NTFS, which is not compatible with a Mac device.
To change the permissions on the USB drive so it is fully compatible with a Mac, the drive must be reformatted.
- Open the Launcher app and search for "Disk Utility".
- Click on the external drive to view the properties. This should show NTFS as the file system.
- Click the "Erase" button at the top to reformat the drive with a different format. Be sure the correct device is selected. NOTE: This should only be done if the information on the drive has already been copied off to another location. Do not format a drive unless absolutely certain there is no information on it, or that the information on it has been copied to another location first.
- In the erase drive window, select the new format type in the drop down list under the drive name. In the example below "ExFAT", which is compatible with a Mac, is selected.
- Once the correct file format is selected, click the "Erase" button in the bottom corner of the window.
- Once clicked, the reformat process will begin.
- When prompted, chose whether or not to use the drive with Time Machine.
- When the drive has been reformatted, click "Done".
- In the disk utility window, the external drive is now listed with the new format.
- Open the Finder app and click on the external USB drive. The properties now show the permissions as custom access.
- Create a folder to verify the permissions are working correctly.
As always, knowing how to use the equipment you already have saves time and money!