Docker Toolbox: Error creating machine: Error in driver during machine creation: Maximum number of retries (5) exceeded
Solution 1:
Had same problem (running docker commands gives error message: No connection could be made because the target machine actively refused it).
There are problems with permissions (likely the target machine was created under a different user account).
This worked for me: Open Oracle VM VirtualBox and right-click the machine named 'default'. If it is running, select "Close -> Power off". Then select "Remove ..." and hit "Delete all files" button.
close Oracle VM VirtualBox and run Docker_Quickstart again. It will create a new default VM with no permission problems.