USB Flash Drive Not Mounting After Mavericks Update

I have a 27in iMac with Mavericks installed. All of a sudden I cannot see any USB external drives when I plug them in, they show up in Disk Utility (and they are unmounted) but not in Finder or on Desktop; when I right click to mount, nothing happens.

I have tried several different USB storage devices, and even used a mac OS formatted drive from my other mac and it doesn't mount either. Not sure if this is related or not, but I also cannot get the built in super drive to mount a CD or DVD. It just thinks about it when I insert the disk then spits it out, never mounting the image from the disk.

I have tried all the tips and suggestions in this thread to no avail. Any suggestions?

David

I was using a firewire cable and my device didn't appear anywhere so I switched it out to connect with a usb cable and have had no problems since. My sugestion is try this before anything else. Im convinced its a problem with the firewire not the external devices.

I have a macbook pro late 2013 with 8gb of ram,bought 2 months ago.also a kingston 16gb usb flash drive with mac os extended,kingston usb drive 16gb with FAT32 and lacie 32gb with FAT32.i have a big folder (1,2 gb) filled with doc,pdf,ppt,txt,htm files and all my usb flash drives plugged on my mac can not be unmount!this happens if i scroll fast the contents of the folder.only the usb stick with mac os extended does not have problem.a few days ago i plugged the lacie stick transfer the folder unplugged it,plug it in and a lot of files where missing and where replaced with a unix executable file of 130mb!and of course after that all the usb sticks (except mac os extended can not be unmounted)

Im really unhappy because its my first mac and with WINDOWS i NEVER lost a file....

PS;no paragon or tuxera installed

I erase my mac and reinstalled maverick 2 days ago for this reason.also sent to apple store which "no hardware problem found with usb ports".they told me to reformat the mac and change FAT32 to mac os extended format on the usb sticks.

No problem with external hard drives 2.5" or other...(either NTFS or EXFAT)

All these sticks are plugged and worked ok on windows (the lacie with the unix executable file shows mambo-jumbo files.but before that was working on windows.)

Also i want to mention that many times when i plug these usb sticks the files are presented not as thumbnails of their content but as white boxes.and when i unplug and plug in the usb sticks are back to normal.or not.....

I believe i came up to a conclusion....i hope so.im writing this post in order to help anyone else who encountered similar problem.

ive done many combination of transferring files to usb sticks 3.0 since yesterday and many formats of them (fat32 and exfat).i didnt check ntfs.i have to mention that with mac os extended there was no issue (ive checked a usb stick many times-a kingston 16gb data traveler G4.there was no issue so i didnt check any other usb stick.).

Also i want to mention that all the usb sticks were accessible through a windows machine at any time.they had NO problem.either on reading files or mounting-unmounting.

i checked the usb stick i mentioned,a lacie xtrem key 32gb ,a kingston 16gb DT R3.0 G2 usb stick and a lacie porsche design 16gb.

All of them USB 3.0.

I used 2 folders to transfer;one containing photos (.jpg) and videos (mp4) 2,61gb and another folder containing ppt,pdf,word files 1,1 gb.

I want to repeat the problem;all the usb sticks i checked (except the lacie porsche design) had problems after copying the above folders (with the usb sticks formatted at FAT32).Could not be unmount (sometimes could not be mount) and after mounting i tried to open the files contained in the folders.It was very difficult.the finder was not responding and when it started responding the scrolling of the items in the folders was very difficult.laggy and very slow creation of the thumbnails (as if the mb pro was having a difficulty to read...) .

At exfat i had no problem (and as i mentioned at mac os extended).only "abnormallity" at EXFAT was that when i arranged items by name,mounting and then unmounting the stick the arrange by name was gone.no arrange was at the items.

One or two times i was not able to unmount the sticks and i unplugged them,not eject them.the result was for some files to lose their "ending" (i dont know how it is called) e.g the .ppt or .jpg and appeared as a unix executable file.(on windows the files were there but with mambo-jumbo names and not opening of cource).

The only usb stick 3.0 that stood well on fat32 or exfat was lacie porsche design.

So i concluded that some usb sticks 3.0 are not "so" compatible with maverics.(USB 2.0 sticks were checked and were OK).

I could say that some of my files are corrupted but all of these files were OK on windows,on usb sticks with exfat or mac os extended and on my macbook pro which i have them saved).

PS;sorry for my long post.

🙂

from another support thread, I tried inserting the USB very slowly, taking like 5 seconds, then it shows up in Finder devices. This is with Macbook Pro from 2007 and Maverick. another non-intuitive feature, just have to use the Mac as little as possible I guess.

Hi Zen

I have been experiencing such problem with my external WD 1TB drive and Toshiba as well after upgrading my OS, did many things but i failed to resolve the problem till i dwonloaded Tuxera drivers for Mac from macupdate.com and finally i can see and browse the content of my hard disc again..it is for free for limited 15 days trial after i guess you have to pay...

Hope this will solve and resolve others same issue

Thanks

This worked for me. THANKS!!!

"1. Unplug ALL DEVICES using USB ports.

2. Reboot the Mac.

3. Plug each device in 1 at a time but wait till it shows plugged in.

This time it should populate in finder and in disk utilities if the finer preferences are correct.

I read that this problem can be was caused by USB mapping error. Those steps above remaps them."

Tried it with no luck.

What I did do that worked for me was I purchased a small USB hub (3 outlets).

Plug that in to the USB port that could not read my USB sticks and now the hub

can populate finder with the very USB sticks that that mac is unable to read.

My issue is truly baffling. I have a mid 2013 13" MacBook Air, and I am using OS 10.10.2. The two SanDisk Ultra USB 3.0 Flash Drives I have mount fine on the machine, and they are also visible in Disk Utility. The 64 gig that I just purchased was originally formatted FAT-32 (I have subsequently Erased and formatted it as Mac OS Extended (Journaled)). I also have an older 17" MacBook Pro that I have OS 10.6.8 on, and it also recognizes both of those Flash Drives (no matter what format). And, once again they show up in Disk Utility (Snow Leopard's version). But, I also have a late 2012 MacMini 2.3 GHz Intel Core i7, and it also has OS 10.10.2. But, no matter which USB port I use, neither of those Flash Drives are "recognized", ie, they do not mount on the desktop, and of course not in Disk Utility. Yet, when I do an About This Mac, click on System Report, then click on USB, and then click on USB 3.0 SuperSpeed Bus, it shows up as "Ultra". Clicking on that does show that it is from SanDisk Corporation.

So, can anyone help me with this?

I think the issue is with the Strontium 3.0 pen drive. I tried in windows 10 ports USB 3.0 and USB 2.0.Only 2.0 port supports pen drive. windows 10 didn't detect the device in port 3.0.