Catalina - External Hard Drives repeatedly ejected without cause.

Is there a solution yet for this issue?? I have searched and found a few fixes but nothing has worked. I am just using a USB thumb drive and it keeps hanging on the importing of photos then suddenly ejects with the warning of improper ejecting of a hard drive. I have a rugged with a cable I need to use but am not wanting to try it for it might damage the contents. Apple help?? Please. I have read posts on this issue since Yosemite. MacBook Pro (Retina, 13-inch, Early 2015) Catalina 10.15.4

Hi Peter, it's definitely a system thing - I've had the same issue since clean install/upgrading from Mojave a couple of days ago - I've resorted to playing a movie from my drive and hiding the window so that the mac doesn't let the connection drop.

When drives were dropping out, I could still see the greyed out drive image in Disk Utility, but was unable to mount them. I had to download a free app called iBoysoft Data Recovery in order to get the drive mounted again.

I've been using macs for 30 years now(!) and it's the same every time - always some glitch with a new system, or some functionality gone - it's very frustrating when the onus is on you - but if everything worked fine so far and only the system has changed, it's likely to be an operating system error. It'll probably be sorted in a version or two, don't dump those drives just yet.

my iMac Pro updated last night to Catalina 10.15.4 and now i'm getting this too. it's making my photoshop work nearly impossible because of scratch disks. i have tried multiple drives with multiple enclosures, as well as all the other solves in this thread to no avail.

I did just download Keep Drive Spinning and selected all but my time machine drive and so far none of my 4 drives have ejected.

I had upgraded my 500GB SSD to a 2TB in my trash can Mac Pro, just to be able to use the thing, as the OWC Raid volume kept disconnecting during use. I'm giving this Keep Drive Spinning utility a try, fingers crossed.

I am having the same issues with a Thunderbay and 2 external WD drives. I will attempt the drive spinning utility, it’s disappointing. Top of the line IMac 2019 and I am unable to use the machine the way it’s intended.

Thank you, It seemed to be a pretty decent product specially now that it has been added to the mac store but I will try to remove it as I prefer my external drives to work, it's extremely frustrating. what's odd is that my issues is with USB not Thunderbolt, the thunderbolt drives attach (Thunderbay 4 and G-Tech Raid drives both on thunderbolt 3) are working fine.

I’ve actually had great results from usb powered external drives over the years. In this case, my drive failures are with a powered tb2 external drive, and the Keep Drive Spinning utility seems to have helped so far, as I’ve had no disconnects since. The problem is clearly an Apple screwup, one which they apparently have determined is not in their interest to fix quickly. I’m happy to have a suitable 3rd party workaround to apple’s bug, but disappointed that Apple has so badly dropped the ball on a serious issue.

I now use Carbon Copy Cloner for that, then I can take the external drive anywhere and access any data via mac or pc. I used to use TM but it's limited... as I unfortunately found out when an old mac died.

I've erased and reformatted drives and there have been no flags and also my drives work perfectly on macs (that are without this issue) and PCs perfectly. Definitely a system fault... or possibly a mac power saving issue.

Ladies & gents - I have found a cure.

After posting on here, contacting Apple chat support (who advised on checking if my thunderbolt 1 WD 4TB drive was 32-bit it 64-bit compatible) I contacted WD support.

Within Catalina, I uninstalled all software & remnants relating to WD, then rebooted.

I then downloaded & installed :-

WD Discovery

WD Utilities

WD Security

from the WD website

Rebooted the system

WD 4TB external Thunderbolt 1 drive is now connected, fully working, transferring & backing up data as it should.

Instead of it ejecting like it was doing after a few minutes, Now every 5 to 10 minutes, there is a slight pause of data transfer, as something refreshes in the background, but the drive remains mounted and fully working.

Mine is an OWC hardware raid box over tb2, a pair of HGST 4tb nas drives, no 3rd party drivers. This approach with WD 3rd party drivers would have no bearing on my device. To reiterate, I’ve used the same external drive box with each macOS release since 2013, and Catalina is the first release where this problem occurs. I installed the Keep Drive Spinning app A week ago, and have not yet experienced a disconnect yet. It usually happened with heavy activity ops, like a big copy, or starting a Linux vm in parallels or VMware fusion, but the KDS app appears to have helped.

I removed all the WD software: WD Discovery

WD Utilities

WD Security

rebooted my system and so far 2 days in the drives haven't disconnected, I did not install the WD software again. my computer recognizes the drives both are USB 3's. keeping my fingers crossed this will resolve the issue, will update if anything changes. to reiterate, each time my computer when to sleep it would unmount external USB 3 WD drives, based on someone sharing I uninstalled all the WD software, didn't download it again. computer recognizes the USB drives perfectly fine, it has woken up at least 40 times without any disconnection for the past 2 days.

My understanding is that Apple puts a priority on addressing new bugs, but largely ignores bugs that have been around for more than a certain length of time. This largely explains issues in macOS such as the random resorting of the widgets in the today view, the random changes in the task bar, and the issues with hard drives that have been around for many many years.

Looks like I spoke too soon when I posted yesterday.... Having had my external drives connected via USB with no problems for a week or so, this morning the machine had shut down with a(another) kernel panic.

It occurred to me that the only thing that had changed since yesterday was that I set up the (new) MacBook Pro to back up using Backblaze, so wonder if the file transfers that triggered had caused the problem.... Will keep an eye on it and report back