Copying a specific folder onto an external SSD, results in ejecting that specific SSD, but not other external SSDs.

Hello @steve626

I did try repairing both the origin SSD and the target SSD. No Problem reported.

I even did reinitialize (format APFS) the problematic SSD. However the problem persisted EVEN AFTER the formatting of the SSD.

"I doubt this is an operating system issue..." so do I but it still remains a mystery. :-)

So to recapitulate:

SSD 1 = Origin drive

SSD 2 = Problematic Target drive

OTHER SSD = Any other SSD used ( I tried 3)

ANY FOLDER = Any other folder except the one that created the problem

SPECIFIC FOLDER = the SPECIFIC FOLDER that creates the problem (preference folder of Thunderbird).

Copy the SPECIFIC FOLDER from SSD 1 to any directory including root of SSD 2 = EJECTS SSD 2

Copy the SPECIFIC FOLDER from SSD 1 to OTHER SSD = NO PROPBLEM

Copy the ANY FOLDER from SSD 1 to SSD 2 = NO PROPBLEM

Copy ANY FOLDER from SSD 2 or OTHER SSD to SSD 1 = NO PROPBLEM

Well it seems I got a ghost in my system that hates that folder :-)

I can't find any other solution. It simply is one of those things. Haha

The only thing that helped in the end, was restoring THAT SPECIFIC FOLDER from a backup.

In any case thx for your time.

Thank you @Old Toad for your help suggestion

However NO MATTER HOW I tried to copy (using other copying software) the folder INTO THE SPECIFIC ssd, including Carbon copy cloner failed.

The ssd is is an WD_BLACK SN850X NVMe SSD 4TB Internal SSD placed in an Acasis Swappable High-Speed SSD Storage & 10-In-1 Hub Docking Station.

BTW when placing any other NVMe SSD in that housing all works flawlessly. As does the specific ssd when copying ANY other file onto it.

In any case thx for your time.

Thank you @etresoft for your help suggestion.

However I probably did not highlight enough the problem.

ONLY COPYING the SPECIFIC folder onto the SPECIFIC SSD creates the problem.

If you copy ANY OTHER folder to that drive OR

If you copy THAT FOLDER to ANY OTHER external SSD drive. there is NO PROBLEM

ONLY IF you copy THAT SPECIFIC folder to THAT SPECIFIC ssd the problem arises.

I know the "method with the halfs" I use it all the time for other things. I used it before posting the whole thing here. However it did not help since the problem appeared while copying a couple of folders included in that specific folder.

And in the end of the day the question remains. WHY does it not occur when copying THAT FOLDER onto ANY other drive?

In any case thx again for your rime.

Thank you @Luis Sequeira1 for your response.

Yes!

Working with Macs since 1984 I know my game (hahahhaha).

However here are 2 screen shots to prove it.

In any case thx for your time.

[Edited by Moderator]

Thx for your message @Old Toad

However this casing I use has more uses than just housing an ssd. Its for me something like a swiss knife.

I carry it with me and use it on my macBook for connecting to ethernet LANs, as a card reader, as a USB A hub, second HDMI port AND as an external ssd. So Im afraid even if i'd replace it, I would need something similar.

Hello @Urquhart1244

Thank you for your thoughts.

The folder is a regular folder no Alias, and not used by the system (only thunderbird).

The problem however IS NOT how to copy the contents. That easy and there are dozens of ways to bypass it.

The problem IS WHY copying THIS SPECIFIC folder onto the THAT SPECIFIC SSD creates a problem, while copying THIS SPECIFIC folder onto the ANY OTHER SSD, or copying ANY OTHER folder from THAT SPECIFIC SSD, does not.

In other words the question is, why does THAT SPECIFIC folder gets copied anywhere else, but NOT ON THAT SPECIFIC SSD.

In any case thx for your time.

Hahahahaha Im afraid you are right... OR for some reasons it got in a quarrel with "thunderbird" and did not tell me.

:-)