How do I get by data back?

Okay, windows 10, I have two cryptomator vaults, one is fine, one shows this behaviour:

Yesterday I noticed that I cannot dir a directory (that contains A LOT of small files. At least tens of thousands.). There seemed to be a sort of timeout: when I entered with explorer or made a dir on the shell, there was a lot of waiting, followed by an error message like “drive not responding”. I could still dir the other directories, but Windows was wonky after that and I kept rebooting and retrying, but to no avail.

I then upgraded to 1.4.5.

Now I can unlock it, but no mounting, and when I do “reveal drive”, I immediately get the box “e:” in unavailaible (E: would have been the letter for the virtual drive).

Now of course I want to get my data back. How can I do that?

(Yes, my HDD ist fine, SMART is fine, etc. Data is backed by dropbox too, so I could get at older versions.)

What version did you use before upgrading to 1.4.5? Are you using WebDAV or Dokany-based vault drives?

Thanks for the quick response.
The old version was 1.3.3.
The previous version used WebDAV, the new uses Dokany.

Were you able to resolve the issue? If yes, what was the solution?