Disks Ejecting While In Use — attention Thunderbolt Drive users!

Has Mac OS X warned you that a volume was not ejected properly even when you know it is still attached?

Have you been warned by the SoftRAID Monitor that there is a problem with your Mac?

If so, you may have encountered a problem which affects disks attached via the Thunderbolt bus. This problem causes older Mac OS X versions (prior to 10.12.2) to think a disk is no longer attached even when it is still plugged in.

Upgrade to macOS 10.12.2 or later

We now know that a problem in the macOS system software is the cause of disks ejecting while in use. This problem is fixed from macOS 10.12.2 onwards.

We strongly recommend that you upgrade to macOS 10.12.2 or any later macOS version if you have encountered this problem. If you are unable to upgrade, you can use the instructions below which prevent the problem in most, but not all, configurations.

After upgrading to macOS 10.12.2 or later, you can re-enable sleep on your Mac. You can also enable the "Put hard disks to sleep when possible" setting in the Energy Saver panel of System Preferences.

Important Note: If you have upgraded to macOS 10.12.2 or later and your disks are still being ejected while in use, we want to hear from you. Please collect a SoftRAID Tech Support Report and send it to our support engineers ( so we can determine if it is a new problem.

We have been working with Apple engineers for over 2 years, investigating and fixing bugs in Thunderbolt, and will continue to do so in the years ahead. It is due to this close relationship that the original problem with disks ejecting while in use was fixed in macOS 10.12.2.

How to prevent this problem in older versions of Mac OS

Turn off sleep in System Preferences:

1. Go to the Energy Saver panel of System Preferences.
2. Uncheck "Put hard disks to sleep..." (see image below)
3. Ensure that 'Prevent computer from sleeping...' is checked (see image below)

We've discovered that, for the majority of users, this solution prevents the 'disk ejecting while in use' problem.

You can find more information about this problem and why it was happening on our FAQ page: Disks Ejecting While In Use.

If you have any questions regarding this issue, please contact our tech support engineers via email by sending a message to:

iMac Pro Users: SoftRAID 5.6.5 driver update problem

Does this happen to you when you try to run the latest SoftRAID on your iMac Pro? :

  • You run SoftRAID 5.6.5 (or 5.6.3) on your iMac Pro.
  • SoftRAID offers to update the driver.
  • The Application stalls on "updating boot cache".
  • When you restart, SoftRAID again offers to update the driver.

What is happening :

High Sierra comes pre-installed with the SoftRAID version 5.6.2 driver. In the new iMac Pro, High Sierra reloads this older 5.6.2 driver, even after the SoftRAID 5.6.5 driver has been installed.

The pre-installed 5.6.2 driver is "limited"; it offers lower performance and cannot rebuild volumes or alert you to disk errors, so it's not something you want to be using. Especially when we have worked hard on all sorts of improvements, bug-fixes and updates for SoftRAID 5.6.5!

This problem was introduced by new security mechanisms in the iMac Pro, which aim to increase the security of your machine. More security is obviously a good thing, but the introduction of these features has the unfortunate side effect of loading out of date kernel extensions—hence the out-of-date SoftRAID driver that keeps getting loaded.

While we work with Apple engineers to resolve this problem, we have come up with a temporary workaround so that you are able to use SoftRAID 5.6.5 on your iMac Pro.

Temporary Workaround

Though not ideal, this temporary workaround is the best 'solution' we can offer at this time :

  1. Unmount your Thunderbay disks.
  2. After 30 seconds, disconnect the cable.
  3. Restart your iMac Pro
  4. Launch SoftRAID and update the driver.
  5. Restart your machine.
    (If SoftRAID stalls "rebuilding boot cache", after a couple minutes, it is safe to force quit SoftRAID and restart.)
  6. Run 5.6.5 again. It should not offer to update the driver.
  7. If you connect your drives now, your volume will mount normally.
  8. Before any restart, unmount your disks. Wait 30 seconds and remove the cable. Do not reconnect your drives until you are restarted. If OS X detects any SoftRAID disks while starting up, it will reload the 5.6.2 kernel extension.

We understand that this is less than perfect but until we can work out a real solution in partnership with Apple engineers, this will allow you to take advantage of all the improvements in SoftRAID 5.6.5 on your iMac Pro.