Mac OS Ventura and exFAT drive format issues

FAQsSituationers wrote:

I formatted to exFat my SSD using my PC but my Macbook Pro doesn't detect it.

My PC reads it instantly so I guess my Mac OS must be the culprit, right?

The problem with formatting a drive with exFAT using Windows is that Windows may use a file allocation size for the file system which macOS doesn't understand. Usually it is best to use Disk Utility to erase the drive if you are going to format it with exFAT. It may be possible to manually specify a file allocation size on Windows when formatting the drive, but I don't know which file allocation sizes macOS understands.

For my situation, I can't use Disk Utility because my Mac doesn't detect the SSD external driver (USB). If it can't see the drive, Disk Utility will never work on it.

Within Disk Utility click "View" and select "Show All Devices" so that the physical drives appear on the left pane of Disk Utility. Unfortunately Disk Utility is very limited especially in its default configuration where Apple has macOS only showing the user the actual usable volumes which in your case it is not usable because the exFAT formatting used by Windows is not compatible with macOS.

If don't see the physical drive after selecting "Show All Devices" within Disk Utility, then there is some sort of compatibility issue with that drive and your Mac (or the adapters, cables, docks, hubs). Make sure to disconnect all other external devices and connect the drive directly to the computer (you may need to try using another adapter if you must convert it, and try using another cable). I know that Macs can be picky about the drives used, and it seems that the Apple Silicon Macs may be even a little bit pickier as well since there was a lot of reports of some third party devices (especially older ones) not working with Apple Silicon. I have seen fewer reports since then, so maybe Apple addressed it with a firmware update or OS update.

If you are using an Apple Silicon laptop, then make sure you are approving macOS to connect the external device.

Allow accessories to connect to Mac - Apple Support

Hi, I'm using MacBook Pro Ventura 13.5.2 It doesn't detect my 30 Tb SSD external drive so I formatted exFAT into it using my PC and transferred some files into it.

The drive size should not matter unless you are using an adapter, dock, or hub, or custom enclosure since these items may be restricted to working with certain size drives. If you have an off the shelf consumer external drive, then size should not be an issue except possibly in regards to adapters/docks/hubs.

FAQsSituationers wrote:

The SSD pilot light just lighst up for a while and then disappears, and that's that. I left it connected to my Mac for an hour, hoping that it only takes some time to detect the drive, but nothing happens.

If you are using an Apple Silicon laptop, then make sure you did not completely turn off access to the USB-C ports in the System Settings. Otherwise, this indicates a hardware issue of some sort. It may mean the laptop is not able to provide enough power to the drive, or maybe the port on the laptop is bad, or the cable for the drive, or an adapter if one is being used, or maybe the drive itself has a problem or just is not compatible with your Mac (happens more often with older drives on the Apple Silicon Macs, but I have also seen it occur with Intel Macs as well since Macs can be picky about the drives used).

Do you have any third party software installed which may be blocking access to the drive or the USB ports? Typical culprits are anti-virus apps, cleaning/optimizer apps, and third party security software. If you are using a Standard (non-admin) macOS user account, then maybe the administrator placed some restrictions on that account. If the computer is being managed, then even an admin account may have restrictions in place.

If you don't see the physical drive listed in Disk Utility even when selecting "Show All Devices", then the file system is not the problem, it is a hardware issue (assuming you did not have macOS ignore the USB-C port connections or have security software or it being managed). If it is a hardware issue, then you will just need to try using another port on the laptop especially on the other side, try using another cable, another adapter, try connecting the drive to a powered USB3 hub in case the drive needs more power (or use a dedicated power supply if the drive supports it). If you still cannot get the Mac to see the physical external drive and that drive works fine on a Windows computer, then it may just be a hardware compatibility issue.

Keep in mind the physical external drive should show up either with the make & model of the drive, or possibly with the make & model of the USB controller used by the drive, dock, adapter, or enclosure. You can also look in the Apple System Profiler to see if the physical external drive or its controller/adapter shows up under USB (or Thunderbolt if it supports the Thunderbolt protocol). Usually in the profiler you will see the external drive's controller and also a reference to the physical storage device within the external enclosure. You can access the Apple System Profiler by holding the Option key as you click the Apple menu and select the first item.

wrote:

It's not a matter of not working, it doesn't even recognize it in the first place.

Do you mean it fails to recognize the physical drive (or this drive's enclosure)? Or do you mean it sees the physical device, but not the volume?

If the latter, then Did you use Disk Utility to erase the drive as GUID partition and exFAT before using it? If the drive was formatted as exFAT using a Windows computer (or a non-Apple system), then it is possible it was formatted with a file allocation size which macOS does not recognize. There seems to be fewer reported issues when using Disk Utility to erase a drive as exFAT.

> I formatted to exFat my SSD using my PC

So try to format it as exFat on the Mac and see if it works better.

I guess GUID partition scheme should work. But when a while ago I tried to use that (exFAT GUID) on 125 GB flash drive, the Windows 10 machine showed only a small (AFAIR 32 GB or maybe even much less) volume while the Mac showed 125 GB free. Using exFAT MBR option in the Mac's Disk Utility fixed that and the whole 125 GB was available also in Windows.

In my setup Windows 10 default exFAT format worked OK AFAIR on Big Sur.

If the drive is not even seen in Disk Utility, then there is something other than the format or even the partition scheme at play.

You said you tried directly and through a hub. It looks to me that the drive is not getting enough power.

Please give more details about the drive, and the cable and hub you were using.

If it is Thunderbolt, you need to use an actual Thunderbolt cable, not a generic USB-C cable.

Sonoma 14.3.1, three different brands of exFat SSD went down. I use Samsung, WD, Crucial.

I have three Samsung t7, exactly the same disks, one out of three works.

I can temporarily fix them when I connect them to PC, and fix the drive. They will reappear. After a few hours, they go down again. Can't install on disk utility. No improper eject. Everything is still in the disk, just that it cannot be detected by MAC.

Time to switch to PC.

Have you installed and run any "cleaning", "optimizing", "speed-up", anti-virus or VPN apps on your Mac?

How is the drive connected?

Direct connect it to your Mac (an adaptor is ok, not a hub or dock). Does it work?

Is the drive self-powered or does it get power from the USB?

I have Ventura 13.4.1 and not only can I format exFAT drives, I can read and write to exFAT formatted drives whether from Windows {10,11} or other versions of macOS.

Do tell us what is not working. As these are strictly user-to-user communities, we would not have any information about any product team activities. At least for me, the first paragraph suggests to me that exFAT works fine and no fix is necessary.

I don't think you ever reported what drive this is, and exactly how you are connecting it.

From what I can perceive of the situation, the drive probably is just not getting enough power.

There is no point in discussing formats if the drive is not even seen by your mac.

FAQsSituationers wrote:

Yes I agree no use talking about formats. I guess it’s a power issue. Is there a way of resolving this? Will plugging power to my Mac help?

No, you would need to plug the drive into its own power supply. Does it have its own power? If so, drawing too much current is not the issue.

That sounds like the drive is pulling too much current and shutting down that port.

Will it help if I connect the SSD USB into a powered USB hub?

Hi, I'm using MacBook Pro Ventura 13.5.2 It doesn't detect my 30 Tb SSD external drive so I formatted exFAT into it using my PC and transferred some files into it.

However, when I connect the SSD thru USB into my MacBook Pro, nothing happens, zilch. I can't use Dik Utility on it because obviously, Mac has to see the drive first. Is this version of Ventura problematic?

I have run disk utility on my mac, it says it is ok.

Luis, nothing happens. My Mac doesn't see the external USB SSD drive. There is no alert, no thing. The SSD pilot light just lighst up for a while and then disappears, and that's that. I left it connected to my Mac for an hour, hoping that it only takes some time to detect the drive, but nothing happens.

I formatted the drive usng my Windows PC under the exFAT format. It should be read but no go.

Could it be a partition issue? Maybe I should create an NTSF partition?