Glad you worked this out. MacOS definitely does not like external Home folders. what you did (aliasing/pointing just the large folders to external volumes, essentially) is much safer.

Finally, I resolved the issue. After 50+ times getting this error message I changed the mount point. In my original set-up the ThunderBlade mounted to

/User/<my-user-name>

Every time this error message appeared MacOS could not handle it, except re-booting. 

After I changed the mount point to

/User/<my-user-name/Pictures/TB-Pictures

this error message vanished completely. 

There are also other reasons, why it is not a good idea to mount to your user directly e.g. if the device is physically not connected you cannot log-in any more.

These are frustrating issues. Thunderbolt runs so fast, even a nanosecond time disconnection powers off the disks momentarily, which will trigger this error.

I will report if the error shows up again

Just because the device appears to be independently connected, does not mean it is. This is a macOS kernel bug where the OS is renumbering devices during sleep. yes, a USB device connected elsewhere can sometimes trigger this. A Thunderbolt bus has two ports on most machines, so while you see two connections, it is the same bus.

We added a check in SoftRAID, when a device wakes from sleep, to make sure the drives have the same "disk Identifier". these change evey time you restart or reconnect the device, they are assigned when the disks show up to macOS. Once macOS assigns a number to a device (disk), it is not supposed to change, ever, until the device is disconnected. When SoftRAID detects this happened, it locks the volume to prevent data corruption.

I am just asking you to test without devices and see what happens. Also, you need to set the System Preferences/energy saver to not sleep.

So do these things:

uncheck "put disks to sleep" in System preferences/Energy Saver

Try using the system without other devices connected when letting the system sleep

(try removing just one, then another, etc.)

This problem can even be triggered by having dual Monitors. Apple is aware of this bug for 4-5 years, but has not fixed it.

What we did was try to protect against data corruption from this issue.

Lets not worry about identifying the drives. I was wanting to see if one drive was being affected in the enclosure, but it is too complicated.In your screen shot, the serial number is identified, I think it is the "seriennumber" field.

Yes, it happens after sleeping. No, there is no USB / TB3 in-between as already described in VERY DETAIL above.  

Which one is the "disk identifier"? This attribute does not appear in your screenshot nor in my. I expect more precision here.

And if I know the "disk identifier" how does it solve the problem?

I did not post the screen shot. Feel free to respond here if you do not get a same day response,every post is answered in less than 24 hours, but it is not a "ticket" system, so sometimes a reply is missed. Apologies for that.

Here is where you can see the disks in System Profiler:

What the volume locking means is SoftRAID is making the volume read only to protect against a data corruption issue in macOS. When you connect your Thunderblade, macOS assigns each disk a "disk identifier", which you can see in SoftRAID's disk tiles (disk2 for example)

These should be permanent until next restart. sometimes, especially waking from sleep, the numbers change without your disconnecting the disks. If SoftRAID wrote to the disks, it would cause data corruption, so SoftRAID checks the disks each wake from sleep to make sure the disk identifier has not changed. If it has, then the volume is locked by the driver.

this is almost always a wake from sleep issue. If there is a momentary disconnection of the enclosure during sleep, etc, then disks are reassigned numbers, but the bug is that the "IO Registry" does not have the new disk numbers.

If you are using a hub or dock, sometimes that can trigger this. Or if you move the computer or any cables during sleep, this can happen.

How often are you getting this? Is it always waking from sleep?

We sent you a response on the spam issue. It is "waiting for customer response". Maybe our last email went to the junk folders?T

The Spamhaus issue is your ISP, not on our end. We cannot do anything about what your ISP is blocking as attachments.

these issues are always a problem, we have several times had "anti virus" companies tell users SoftRAID contained a virus (it never has, and everything we release is code signed by Apple) which is time consuming to deal with.

The initial emails to support cannot contain attachments. However, responses can have attachments, as a case has been opened.

We could probably add Png files. What is really needed for helping users are Tech Support files. I 100% prefer Tech Support files.

Let me post a screen capture for you to look at. It will take a few hours.

@softraid-support

this one?

If you click on the Sata/Sata Express tab, you should see each disk listed. the serial number is on the 4th line in the lower window.