I’m just an avast user like yourself.

I don’t understand how they can go missing either as essentially they should have been isolated. But if you were able to connect to the dropbox anything that you did would be discarded when you closed the instance of junction.exe running inside the the sandbox. This may have resulted in the actual content in the dropbox also being discarded, so the sync feature in dropbox would set all to the same.

I can try to draw some attention to this topic.