The following runtime error stack can occur when attempting to open a database:
   1024 Cannot open structure of database Database Name
   650 Folder "{name}" not found ({path}).
Where Database Name is the name of the database being opened.

Runtime error stacks are ordered in reverse chronological order. So the bottom most issue is the inital cause of the problem:
   650 Folder "{name}" not found ({path}).

A potential cause of this issue on Windows is a Windows update that requires a restart to complete. The issue can be solved by performing the restart and allowing the update to complete.