Allow Access External Drives Macos

When I bought the WD My Passport Ultra drive, I was surprised to see that it didn’t support OS X out of the box. Yes, it had some software specifically made for OS X on it, but even that didn’t help. Turns out, it just wasn’t in the right format. These hard drives are customized to run well on Windows (as you’d expect), and they don’t run well with OS X.

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So to get it running, what we’ll need to do is format it in Journaled format, which is OS X only format or MS-DOS (FAT), which means it will run with both OS X and Windows. If you’re only going to be using the hard drive on a Mac, I recommend you stick with Journaled.

Sep 12, 2020 Mac OS Extended: Works only with Mac OS. Completely incompatible with Windows computers. This is the best option if you intend to use your external hard drive exclusively with computers running Mac OS. NTFS (Windows NT Filesystem): Works natively with Windows, Mac OS write-capability can be added using the steps in the previous Method. Jun 25, 2021 The best way to look for an incorrectly formatted drive is to go to. Apple (in the top toolbar menu) About This Mac Storage. See if the external drive shows up here. For more information, go to the same menu option, then select System Report. Mac not formatted to display external drives on the desktop.

Why You Need to Re-Format the External Hard Drive

  • How to Install macOS High Sierra on the External Drive. Mar 03, 2020 Step 1: Formatting the External Drive To allow the external drive to function as the startup disk, you need to format it to Mac OS Extended and employ GUID partition map. Start the utility disk. You can find it under the Applications category or search it using Spotlight.
  • Nov 01, 2021 Go to Applications. Launch the “Install macOS Monterey” app. Click Continue and then Agree. When you arrive on the drive selection screen, click Show All Disks. Select your external hard drive and click Continue. Select a user to set as the owner of the new volume and optionally copy the user’s account settings.
  • Apr 12, 2012 Easiest way is to type the command cd followed by a space, then drag the icon for the external onto the Terminal window, then hit the return key. You can also find the path using the mount command and enter that after cd. Then you should be able to navigate to the.Trash folder and do any copying or moving you need to do.

When I first got the hard drive, I wasn’t able to copy anything over to it (but I was able to copy from it). Disk Utility showed that it was formatted to MS-DOS (FAT) but I’m pretty sure it would have been NTFS instead. If you experience the same issue, your only recourse is to reformat it in one of two formats.

If you’re only going to use the external hard drive with Macs or you want to use it for Time Machine backups, format it in Mac OS Extended (Journaled). If you’re like me who also needs to use at least a part of the hard drive from Windows PCs, you’ll need to choose MS-DOS (FAT) format. But here you won’t get great support for Time Machine. Plus you can’t make partitions bigger than 2 TB or move files larger than 4 GB around.

How to Re-Format the External Hard Drive

First, connect the external hard drive, bring up Spotlight Search by using the keyboard shortcut Cmd + Space and type in Disk Utility. Press Enter and Disk Utility will launch. You can also find it in Utilities folder in Applications.

Now, from the left column select 1 TB WD My Passport (or whatever your hard drive name is), and click on the Erase tab.

From here, in Format, select Mac OS Extended (Journaled), give it a name if you want, and click Erase.

You’ll get a warning. Again, click Erase.

In a couple of seconds, you’ll have an OS X ready hard drive to go.

Related: Check out our Ultimate Guide to OS X Yosemite.

How to Create Partitions

Portable external drives

I’m planning on using my hard drive for both Time Machine backups and to carry media files around. I might need to use the hard drive with Windows computers so I’m going to format one of the partitions as MS-DOS (FAT), fully aware of its limitations. The other one, for Time Machine backups, will be in Mac OS Extended (Journaled) format.

To create a partition, select the hard drive from the left column and click the Partition tab.

Allow Access External Drives Macos

From the drop-down below Partition Layout, select the number of partitions you want. Don’t go overboard here.

Now, just below, you’ll see a visual representation of the partitions. You can use the breakpoint to change the size of the partitions by moving it up or down. You can also click on a partition, give it a name and select the format.

Once you’ve decided all the details, simply click the Apply button. From the pop-up, select Partition.

Disk Utility: Check out the two tips for using Disk Utility and 8 ways to free up space on your Mac.

What Do You Use It For?

What are you planning on doing with the external hard drive? Time Machine backups perhaps? Or just storing media? Share with us in our forums section.


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6 Best Ways to Fix Notifications Not Working on Mac

Are you facing notification getting delayed or not working on #notifications not working on Mac.

Hello Nasir,

Having a running OS off of an external drive is not usually recommended, so I strongly advice against it.

You can solve the absence of having an OS on your Mac by following the following steps.

  1. Ensure your MacBook Pro is connected to a reliable wifi source that can hold up for about an hour.
  2. Power off your MacBook Pro and then power it on.
  3. As soon as the MacBook Pro is on and the background sound is heard, hold down the Command (⌘) – Option (⌥) – R combination of keys.
  4. This will get you into internet recovery mode, which should be a grey logo of a globe.
  5. After the internet recovery mode is all loaded up, click on the reinstall macOS High Sierra.
  6. Clicking this should take you to a screen where you chose the disk you would like to install macOS High Sierra on. click on Macintosh HD at this point.
  7. After completing the basic formalities of agreeing to the terms and conditions, installation of macOS High Sierra will begin.


Portable External Drives

The installation of macOS High Sierra is highly dependant on your internet speed. With 150 Mbps of internet speed mine took about half an hour.


Allow Access External Drives Macos Os

When I reinstalled macOS, I got an error saying 'Couldn't create preboot volume for APFS' if you encounter a similar error you can reply to this post.


Hope this was helpful!!!


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Jan 3, 2019 7:11 AM