Workspace sees drives but does not access them

[DARsound]

The title of the thread is one part of a bigger problem I cannot find the origin or solution.

I finished the sound editing on a documentary a few weeks ago, changed absolutely nothing on my setup and today was about to start a few corrections and premixing and the first thing not working is Import Audio menu, as soon as I open the folder with the files to Import in comes the wheel of death. Force Quit.

Initially thought it had to to do with mixed formats (aiff, flac) so I converted them on a different computer and started opening an OMF sent by the director with extra files to add. (OMF had worked fine on this project, several times). Audio files not found, Relink window opens (so far so good), when I start browsing to the exact folder to be searched, Relink window opens one folder (arrow down) and that´s it. All other content (drives and folders) is not available although the arrows move down. Opened workspace and the drives were not there, Task Manager was taking ages at "Synchronizing folder contents" or "Expanding Tree". What is happening here? Thankful for any hints.

Running PT 2023.6, Mojave, Mac Pro 5.1

EDIT: OS X Activity Monitor mentions Pro Tools Quick Time Server NOT RESPONDING, fwiw

[Guy McDude]

I had a kinda similar thing tonight.

PT "warned me" that the session I wanted to open, [ one thats been opened HUNDREDS of times] was not on a record volume, telling me to change it to a record volume.

Here, for some reason, it was looking to my internal backup drive when i opned this session.

I unmounted the internal backup, the error/ workspace prompt went away.

not sure what would cause it look at that drive, and NOT initially see the drive with the session file, and complete audio files folder.

"pro tools, 60% percent of the time, it works everytime"

[DARsound]

I opened the backup session I had on another drive and it works as usual, so I suspect the original harddrive is the culprit. Not sure why it would suddenly stop being friendly to PT, but I'll just avoid it from now on. I suspect one feature PT might not like is the automatic sleep mode which I cannot switch off on that particular hd, but who knows. Thanks for the reply.