MacBook Air unable to read an exFAT-formatted external hard drive

[Chip Boy]

Hello everyone,


I bought a Toshiba Canvio Basics external hard drive with 2 TB of storage some weeks ago. I formatted it and chose the exFAT system. I currently have more than 700 GB of important data saved in that device. Whenever I connect the external hard drive to my tiny, cyan-colored HP Stream, the PC manages to read the device instantly, even if the computer resembles a child's toy and has a mere 2 GB of RAM memory. Several seconds pass (no more than 10) and I am ready to browse the contents of the drive at leisure.

However, every time I try to connect that same external hard drive to my sleek, modern MacBook Air, the transmission seems to stall from the very beginning and can take almost 60 minutes to load. Of course, I checked the format and it is still exFAT indeed. After the hour has passed, a golden-coloured external hard drive icon shows up. When you click on it, you are again subjected to extreme torture in the form of another insane amount of loading time until the folders and icons finally show up, if they do at all.

I read the forums and see that everybody is recommending making a backup copy and giving a new format to the external hard drive. But my problem is that I have no space whatsoever on my MacBook Air (my flash storage is limited to 128 GB of space) to create a backup copy. I did buy another Toshiba Canvio Basics external hard drive, but I haven't even touched it, out of fear of choosing again an exFAT (which is thought of as compatible and able to be used both on Mac and PC) format again and risking to spoil a piece of hardware.

Whenever I think about the causes of this malfunction, I guess it might have something to do with how the disk was formatted. I did some reading and consulted several online tutorials in order to do it properly, but I cannot declare with complete conviction that I knew how to properly manage the Scheme menu (I guess GUID should be the one to choose) or, again, how to choose the right unit allocation size (apparently, the amount of kilobytes one chooses can have a huge influence on the functioning and the reading speed of the EHD).

Note: I admit that the idea of connecting my two EHDs to my MacBook and transferring all the content from one EHD to another actually crossed my mind, but I don't think my computer has enough force to do that task. Loading a single EHD seems like an excruciatingly hard labour for my MacBook, so I cannot imagine the stress when it has to deal with two external hard drives. Besides, what kind of guarantee do I have if I format the new EHD again using exFAT, as it has proven terribly unreliable in the past?

• MacBook Air (2019 model)
• 13'3 inches Retina Screen
• 8 GB RAM Memory
• 128 GB Flash storage memory
• 1,6 GHz Intel Core i5 (I5-8210Y) double core
• Monterey (version 12.4) Operating System

What should I do? Could someone of you please give some advice or offer me some help?


Thanks for your help and advice.


Rainbowlight

 

[g35]

I had a problem with my M1 air that it couldnt work with an old external HD, the USB controller in it was too old for the new Mac or something. I wonder if that could be the issue here, that the drive, even if it’s a new model, uses an old kind of controller that the newer macs don’t like.

Also - if using one, could your USB-C dongle be to blame? Can you try a different one? Maybe it’s not passing enough power to the drive or something

 

[Chip Boy]

I had a problem with my M1 air that it couldnt work with an old external HD, the USB controller in it was too old for the new Mac or something. I wonder if that could be the issue here, that the drive, even if it’s a new model, uses an old kind of controller that the newer macs don’t like.

Also - if using one, could your USB-C dongle be to blame? Can you try a different one? Maybe it’s not passing enough power to the drive or something

I actually bought a special cable that connects the external hard drive to the Mac without the need for a hub. The result remains the same.

As for the Toshiba external hard drive, it is a brand new model, apparently equipped with a 3.0 technology that helps to speed things up. Of course, the store where I bought it is completely reputable. Should I go to my nearer Apple Store to see if they have a solution for this problem?

Thanks for your answer.

 

[dwig]

Apple's implementation of exFAT is notorious for balking at minor errors in the drive's file structure, errors that Windows can handle and often without bothering the user.

I'd suggest attaching the drive to the Windows machine and accessing the Properties panel for the drive (right click on the drive's icon and select Properties from the menu). Once on the Properties panel, select Tools and use the Error Checking option the panel to see if Windows can detect and fix any errors. If it finds any, let Windows fix them and then unmount the drive and test it on your Mac.

 

[Chip Boy]

Apple's implementation of exFAT is notorious for balking at minor errors in the drive's file structure, errors that Windows can handle and often without bothering the user.

I'd suggest attaching the drive to the Windows machine and accessing the Properties panel for the drive (right click on the drive's icon and select Properties from the menu). Once on the Properties panel, select Tools and use the Error Checking option the panel to see if Windows can detect and fix any errors. If it finds any, let Windows fix them and then unmount the drive and test it on your Mac.

Thank you so much for your help.

I have one minor doubt, though. I'm a complete newbie. As I understand it, the time the computer takes to read the EHD (from the moment the EHD is connected to a computer to the appearance of the golden icon) is called "to mount".
What is "unmounting" a drive, though? How is it done? Will it harm my files?

Thanks again for your help.

 

[Chip Boy]

Apple's implementation of exFAT is notorious for balking at minor errors in the drive's file structure, errors that Windows can handle and often without bothering the user.

I'd suggest attaching the drive to the Windows machine and accessing the Properties panel for the drive (right click on the drive's icon and select Properties from the menu). Once on the Properties panel, select Tools and use the Error Checking option the panel to see if Windows can detect and fix any errors. If it finds any, let Windows fix them and then unmount the drive and test it on your Mac.

I did as you told me. Sadly, after five minutes of checking the drive for errors (progress bar completely blank through the whole process), a message popped up saying Windows was unable to complete the process. Went to Windows Event Viewer to see if anything was wrong and there was a line of text regarding some kind of error (excuse my the vagueness of my language, but I just cannot comprehend most of I.T. language).

 

[Chip Boy]

Apple's implementation of exFAT is notorious for balking at minor errors in the drive's file structure, errors that Windows can handle and often without bothering the user.

I'd suggest attaching the drive to the Windows machine and accessing the Properties panel for the drive (right click on the drive's icon and select Properties from the menu). Once on the Properties panel, select Tools and use the Error Checking option the panel to see if Windows can detect and fix any errors. If it finds any, let Windows fix them and then unmount the drive and test it on your Mac.

While the EHD was connected to the Mac, I ran the drive through Disk Utility.First Aid seemed to find no problems on the main external hard drive. However, when I ran the sub-drive (the one that actually appears as an icon on the screen), a message came up saying the volume could not be unmounted, thus rendering the reparation impossible.

I have attached an image of the message, so you can a haver a clearer idea of the problem.

 

[Ruggy]

You asked about unmounting a drive.
The best way is to rt click on the icon (hold control key and left click is also rt click) and you'll see options in the menu there to 'eject'
In finder you should also see the drive in the list (although you might not have the option to show external drives in the list enabled) and you just have to click on the arrow.
You are supposed to unmount a drive and this goes for Windows too. If you don't then it can corrupt- something. I'm not sure what but it does happen if you just pull them out for instance.
Sometimes, you have no choice however if they won't unmount and it probably won't even let you shut down the machine in which case hold the powr button down for about 10 seconds until it shuts off.

 

[nowwatch]

I have been hampered wby my exFat external drives continuously disconnecting on my M1 Max since the Ventura update. I have run first aid on them as well and it shows no problems. The drives either fail to mount, even though they show up (greyed out) in the disk utility, or they disconnect every 3-4 minutes, making it impossible to work on a project. They work fine on the PC, and worked fine on mac before Ventura. Please Apple! Address this issue and find a resolution.

 

[HDFan]

Please Apple! Address this issue and find a resolution.

There are a lot of threads about unexpected disconnects. Apple probably does read these forums, but if you want any response from them you would need to contact Apple support to at least add to the list of user experiencing the problem.

 

[BrianBaughn]

I don't think anyone's said it yet but I would not advise putting "important data" on an exFAT-formatted drive when used in conjunction with macOS.

Also, there's another recent thread on here where someone has discovered that when they use the macOS Finder to copy files between folders on their exFAT drive that the copied files have new creation and modification dates…yet another thing I wouldn't want for "important data".

 

[MBAir2010]

I have not figured out what can read what anymore!

this MacBook Air 2021 wont read AFPS or that formatted system on older external USB3 dives
but will read a Mac Journaled with a USB_a or b (the with the weird double slat connection thing to the drive)
so I just use what the MacBooks want to use!