Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
I had a similar issue with mine. It was in the process of encrypting, and the El Capitan disk utility wouldn't allow it to be unlocked via password (kept shaking). Current work-around is to unlock the drive on a non El Capitan machine (I used a VM of Yosemite on my El Capitan machine). I was originally afraid that it had bricked the drive, but glad to confirm it's related to the known release issues and not a hardware problem.
 
I had a similar issue with mine. It was in the process of encrypting, and the El Capitan disk utility wouldn't allow it to be unlocked via password (kept shaking). Current work-around is to unlock the drive on a non El Capitan machine (I used a VM of Yosemite on my El Capitan machine). I was originally afraid that it had bricked the drive, but glad to confirm it's related to the known release issues and not a hardware problem.
If the encryption breaks from version to version, it would be annoying since each time encrypting and decrypting a large disk would surely need hours to complete. :(
 
I had to manually mount the drive in disk utility, seemed to work after that:
84daQ7D.png
 
I've tested this with 2 external hard drives I own, both drives do not show up when plugged in. One is USB and the other is Firewire 800. Anybody else seeing this?

Yes i am currently having the same problem with my Seagate backup plus 1tb (usb 2.5') drive suddenly not working on my 13' mbpro 2015. The drive does not work on either USB port and does not show up in disk utility but the drive is healthy and works fine on other computers.

Does anyone have an update?
 
I hope they fix this before they release El Capitan on the 30th. I was hoping to do a clean install and manually restoring backed up files...
 
hello!! I have a problem here and i am going crazy I'll show what happens to me and the external hard drive i have (samsung)

Captura de pantalla 2015-10-02 a las 21.08.48.png
Captura de pantalla 2015-10-02 a las 21.09.06.png


I don't know what to do to be able to use it. Hopefully someone knows what is going on

thanks in advance
 
This is why we never upgrade to a new OS until 2-3 updates. It's foolish to go out and install on the first day
 
Believe I know I shouldn't have but I did not check when it was realeased to be honest saw it and updated it. But please do you know how I can solve my problem
 
I've tested this with 2 external hard drives I own, both drives do not show up when plugged in. One is USB and the other is Firewire 800. Anybody else seeing this?
I upgraded yesterday and found the message external disk was disconnected improperly. I did not disconnect it from the USB drive. The icon on my screen would disappear, then it would reappear. I was able to get it to do backup but this has been happening all day. What is the cure? I suspect the cure is the next upgrade. I checked my disk utility in Applications and my external drive is listed there.
 
Last edited:
I had this problem as well - my late 2013 iMac did not recognize external USB drive after I upgraded to OS X 10.11 El Capitan. After restarting several times with no success, I moved the external drive to my Airport Extreme base station, which has a USB port of its own, and I was able to access it via WiFi in Finder.

Subsequent to that, I moved the external drive back to the USB port on my iMac, and voila, it finally appeared on my desktop and in Finder, like normal. Not sure if moving it to the Airport Extreme to access it wirelessly had anything to do with it, but I thought I'd post this, in case it helps someone else. Do know, at least, that you can access your external hard drive data via WiFi if you really need to get to it.

One last thing: I called AppleCare, and they're aware of this issue and are working on it. I'm guessing there will be a 10.11.1 release soon.
 
We need more info to help.

Is Finder > Preferences > General > Show Items on the Desktop > External disks checked?

If it IS then check that the drive is being mounted. In the terminal:
Code:
ls /Volumes/

or

Code:
diskutil info -all
(And look for "Mounted Yes" under your volume

If its NOT listed there then check it is being recognised. In the terminal:
Code:
diskutil list

So i did all this, i can see my NTFS disk on disk utility and it is being recognised but when i ran the code to check if it's being mounted then it didn't show up.
 
After upgrading to el capitan this week my mac mini did not recognize my external HDD.I connected ex HDD to imac running maverick a it showed without problem.I ran disk utility on ex HDD and formatted it,just in case.
After connecting to el capitan,mac mini asked me if I want to connect to mac or my virtual machine.
I choose my mac mini but I could't see my ex HDD in finder or disk utility.Then I checked my system informations and it showed ex HDD connected to USB 3.0 Bus.Then I opened Forklift app and ups my ex HDD is there.So what is going on Mr Finder??? After I copied small file to ex HDD via Forklift app suddenly it showed in finder and disk utility.
 
Yeah this crap is still happening to my external drives. They work 100% fine in Yosemite, but after upgrading they won't mount anymore. They mount fine on another computer still running Yosemite. This is ridiculous. They didn't work in the beta and now they don't work with the official release. Good job, Apple.
 
  • Like
Reactions: paulCC
Same thing here. El Capitan won't see external USB drive that was pretty much functional in Yosemite. Restarting doesn't help. They should have warned that they were releasing beta.
 
So helpful when people chime in with the problems they're not having in a problem thread.
well, actually it is useful to know this isn't a widespread issue ...

BTW Im having issues with USB peripherals on El Cap. I basically can't create a bootable USB stick (tried 3 different brands)
 
We need more info to help.

Is Finder > Preferences > General > Show Items on the Desktop > External disks checked?

If it IS then check that the drive is being mounted. In the terminal:
Code:
ls /Volumes/

or

Code:
diskutil info -all
(And look for "Mounted Yes" under your volume

If its NOT listed there then check it is being recognised. In the terminal:
Code:
diskutil list

I've got the same problem, my iomega 500gb eGo USB external HDD does not appear in the Finder or even in Disk Utility after I upgraded to El Capitan.

I followed your suggestion using the Terminal and it seems to recognise it only when I typed
Code:
diskutil list
[/QUOTE]

I can't access the HDD at all though.... can you help?
 
Can't see this anywhere else but my Superdrive isn't mounting since installing El Capitan. Anyone else having this problem? (2015 MBP, clean installation of El Cap)
 
Can't see this anywhere else but my Superdrive isn't mounting since installing El Capitan. Anyone else having this problem? (2015 MBP, clean installation of El Cap)
I just called Apple who helped me solve the problem buy holding down shift, alt and command then hitting power button. MacBook didn't turn on but apparently this changes they way El Capitan looks for these devices... sounds strange but the HHD is currently backing up... the only other thing that could have helped was I plugged it into my old laptop which is running Yosemite...
 
it seems that the os is trying to repair the external disk (see the fsck_??? process in the activity monitor - with 99%) from the moment it is connected in the usb. I killed the process and the disk were mounted but in read only mode. After that I reconnect the drive and waited for the process to end, and after some minutes (~10) it appeared mounted on the desktop.
 
  • Like
Reactions: Goatllama
it seems that the os is trying to repair the external disk (see the fsck_??? process in the activity monitor - with 99%) from the moment it is connected in the usb. I killed the process and the disk were mounted but in read only mode. After that I reconnect the drive and waited for the process to end, and after some minutes (~10) it appeared mounted on the desktop.

After the long wait, I never encountered the same problem with the external disk again.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.