Cant unlock vault

I created a vault and put some test data in. It has disappeared from my network locations. There is no option to unlock it.

All I can do is create a new vault. If I try to open this vault with the password, it says vault not empty. I have tried clicking on the vault - + - open existing vault and then navigating to the encrypted folder with the master key but nothing happens.

I guess this is also the known OneDrive - Files On Demand Issue.
See here:
or here: Unable to use OneDrive with Files On-Demand enabled

Please try to deactivate the files-on-demand option and test again.