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USB Thumb Drive - Macbook Pro cannot read

Hi - I have a question about an USB Thumb Drive I have.


I have a USB thumb drive currently format as MS-DOC (FAT32). It has always been on my MacBook Pro (version: Early 2015) running MacOS Catalina 10.15.6 as additional external storage.


I was trying to use this thumb drive on another older MacBook Pro (version: Mid 2010), running MacOS Yosemite 10.10.5 to read and store/copy some files. It was working fine and I managed to copy the files onto this thumb drive.


However, when I unplug this thumb drive from the Mid 2010 MBP and plug it back into Early 2015 MBP, the Early 2015 no longer reads the thumbdrive and it would not show as an external drive on my Finder.


But now If I plug this back into the Mid2010 MFP, it reads fine and I can see it in the Finder.


Any idea why this is happening and how can I make this USB thumb drive readable in my Early 2015 MBP again?


Thanks,

YGI

MacBook Pro 17″, OS X 10.10

Posted on Sep 6, 2020 9:54 PM

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5 replies

Sep 7, 2020 1:07 AM in response to YouGoodInch

YouGoodInch Said:

"USB Thumb Drive - Macbook Pro cannot read: [...]When you say 'reset SMC and NVRAM', you are talking about my early 2015 MBP right?[...]

———-


I am referring to all Macs have this issue.


Format Types:

  • FAT32 is for Windows.
  • macOS Extended is the Format for a 2010 Mac.
  • ASDF is the Format you need for a 2015 Mac.


Get a Mac-Compatible Flash Drive:

So, if the the resets don’t work on the Mac(s), use a new flash drive — one labeled as “Apple Compatible” right in the original packaging. Get one at your local retailer.


Transfer Data Over:

Using the computer that works, plug both Flash Drives into it, Drag-and-Drop these files from between the two devices: From the current Flash Drive to the new flash drive.


Point Being: With the new Flash Drive, All Hold be on it, and you would be set from here.

Sep 7, 2020 10:57 AM in response to YouGoodInch

I've seen some really odd behavior with macOS and USB sticks similar to what you are describing. We had a USB stick formatted on one Mac (computer1), but the USB stick would not be recognized at all on another Mac (computer 2) with identical hardware, but a different version of macOS. Even if we formatted the USB stick using the other Mac (computer 2) the USB stick still wouldn't be recognized on (computer 1). We did determine that the USB stick did have intermittent hardware issues of some sort, but the USB stick "seemed" to work fine when used with only one Mac.


Macs are very picky about the USB sticks used. Plus the quality of USB sticks is extremely poor even when using a USB stick from a well known "reputable" brand.

Sep 6, 2020 10:18 PM in response to YouGoodInch

YouGoodInch Said:

"USB Thumb Drive - Macbook Pro cannot read: [...]Any idea why this is happening and how can I make this USB thumb drive readable in my Early 2015 MBP again?"

-------


Reset the SMC and your NVRAM:


I. Why this Occurs:

Probably because a cache was modified in a recent application used along with the drive. Sometimes, when changes are made to the system(i.e. updates), system configurations (i.e. for Ports) become manipulated, technically. So, reset the SMC and NVRAM. Your power adapter may not be being seen promptly by the ports, or your battery may not be charging affectively. By reseting these, all of the ports would be configured to how they should be.


II. Perform this Thrice:

Note that you may need to perform each thrice. This can be time consuming, to be certain you have the time to do so.

USB Thumb Drive - Macbook Pro cannot read

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