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User profile for user: MutantBikes
MutantBikes Author
User level: Level 1
7 points

Mac can't see USB drives & External drives

Since updating to Monterey (I think), external discs aren't showing up.


Tested drives on other mac, they show up.


Directly plugged to USB instead of Thunderbolt, still no drive.


Rebooted iMac, still no drives. Will not even see USB Flash drives.


Printer, scanner, and extra mouse all work fine through USB connection.


iPhone shows up when plugged in through USB.


Finder Preferences: Show External Drives is checked


Disk Utility (First Aid): Does NOT show "external" header for external drives in left menu column, "Internal" drive list shows Macintosh HD, my main hard drive.


I need to make a back up before I can wipe and start over but I can't connect a drive. Ugh.


Ideas? Thanks!

iMac 27″, macOS 12.5

Posted on Nov 14, 2022 6:07 PM

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User profile for user: HWTech
HWTech
User level: Level 9
60,554 points

Posted on Nov 18, 2022 3:58 PM

Keep in mind that the most common apps to cause problems with macOS are anti-virus apps, cleaning/optimizer apps, and third party security software. Also, if you are using a third party app to manage an NTFS drive could also cause a problem as maybe it is interfering with normal macOS drive operations somehow (doubtful to interfere with non-NTFS volumes, but you never know).


Another possibility is that some third party connected devices may not be compatible with the latest update/upgrade. I have seen several reports where a connected Wacom tablet can cause USB drive issues if the tablet is already connected when the USB drives are connected later (a user said if the Wacom tablet was disconnected, then a USB drive would mount fine and the tablet could later be connected and the drive would still function -- it was the order of the connections). I'm only using the Wacom tablet as a known example as other devices may cause a similar problem. Safe Mode would disable a proprietary driver for external devices.


As for the screenshot of the error message for the "YES_RED" drive, I did find this article which mentions the "disenter 49223" error is likely caused by trying to mount an exFAT drive that was formatted with Windows. Windows may use a file allocation size for exFAT which macOS does not recognize. If you want to share exFAT drives with macOS & Windows, then erase the exFAT drive using Disk Utility which should allow the exFAT drive to work with both macOS & Windows.

https://www.macgasm.net/news/com-apple-diskmanagement-disenter-error/


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User profile for user: HWTech
HWTech
User level: Level 9
60,554 points

Nov 18, 2022 3:58 PM in response to MutantBikes

Keep in mind that the most common apps to cause problems with macOS are anti-virus apps, cleaning/optimizer apps, and third party security software. Also, if you are using a third party app to manage an NTFS drive could also cause a problem as maybe it is interfering with normal macOS drive operations somehow (doubtful to interfere with non-NTFS volumes, but you never know).


Another possibility is that some third party connected devices may not be compatible with the latest update/upgrade. I have seen several reports where a connected Wacom tablet can cause USB drive issues if the tablet is already connected when the USB drives are connected later (a user said if the Wacom tablet was disconnected, then a USB drive would mount fine and the tablet could later be connected and the drive would still function -- it was the order of the connections). I'm only using the Wacom tablet as a known example as other devices may cause a similar problem. Safe Mode would disable a proprietary driver for external devices.


As for the screenshot of the error message for the "YES_RED" drive, I did find this article which mentions the "disenter 49223" error is likely caused by trying to mount an exFAT drive that was formatted with Windows. Windows may use a file allocation size for exFAT which macOS does not recognize. If you want to share exFAT drives with macOS & Windows, then erase the exFAT drive using Disk Utility which should allow the exFAT drive to work with both macOS & Windows.

https://www.macgasm.net/news/com-apple-diskmanagement-disenter-error/


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User profile for user: HWTech
HWTech
User level: Level 9
60,554 points

Nov 15, 2022 5:37 PM in response to MutantBikes

Try booting into Safe Mode to see whether the physical drives are seen for the external drives. Safe Mode prevents the automatic launching of third party software during boot & login.


You can also boot into Internet Recovery Mode to see whether the external drives are seen with Disk Utility (again make sure to select "Show All Devices"). You can try using Command + Option + R to access the Ventura online installer and Command + Option + Shift + R to access the online installer for the OS which shipped from the factory (likely 10.15). This will remove all third party software from the equation as well plus any possible configuration issues as well as allowing you to easily see if Catalina has an issue which would imply a hardware issue.


This is all about seeing the physical drive at this point because the physical drive is not appearing in your screenshot of Disk Utility.

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User profile for user: MutantBikes
MutantBikes Author
User level: Level 1
7 points

Nov 15, 2022 3:20 PM in response to HWTech

Thx HW Tech!


File system on the main backup drive: Mac OS Extended (Journaled)


Make & Model: WD, EasyStore - 4T


This iMac: Retina 5k, 27", 2019 / Processor: 3.6ghz 8-Core Intel i9 / Memory: 64 GB

OS: Montery (12.5.1)



iMac that can access drives: iMac 27", Late 2012 / Processor 3.4ghz Quad Intel i7 / Memory: 24 GB

OS: Catalina (10.15.7)


Drive was working with this iMac until Sept 7, 2022 - Last back-up was Sept 6th.


Disk Utility: Show All Devices = only shows internal drives. External drive connected with light activated at the time of this screen shot.


Other flash drives that did not work now, had worked in the past on this machine.


Also a USB / SanDisc reader adaptor is not mounted when inserted. Worked previously.


Thanks!

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User profile for user: MutantBikes
MutantBikes Author
User level: Level 1
7 points

Nov 17, 2022 11:43 AM in response to HWTech

Sorry for the lag... I did a Safe Mode restart and was able to see the drive (Mutant_4T). My USB drives, however, are not mountable. MS-DOS (FAT32) are not mountable any more? I cannot reformat the SanDisc for my 3D printer so I guess I'll have to sneaker net to my PC for that one.



This was the error when trying to mount the USB's:


I restarted normally and yep, the 4T drive is gone again.


Next steps? Try to figure out which 3rd party app is breaking stuff? GO back to an older OS? I'm afraid of Ventura, it's a little too new for my comfort. I'm waiting until 13.1 at least.


Thanks again for your help!!

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User profile for user: HWTech
HWTech
User level: Level 9
60,554 points

Nov 15, 2022 12:31 PM in response to MutantBikes

What file system is on these drives?


What are the make & model of these drives?


What is the exact model of this Mac and the ones which can access the drives? You can get this information by clicking the Apple menu and selecting "About This Mac".


Did these drives ever work on this particular Mac?


Within Disk Utility click "View" and select "Show All Devices" to see whether the physical drive appears on the left pane of Disk Utility.

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Mac can't see USB drives & External drives

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