After upgrade: An unexpected error occurred while loading the vagrant-login plugin.

[Paul Sijpkes]

I just upgraded virtualbox and vagrant on OS X El Capitan and I get this error.  I've run the repair and expunge commands but this issue still occurs. 

An unexpected error occurred while loading the vagrant-login

plugin. Please contact support with the following

error code: '7'.

Vagrant failed to initialize at a very early stage:

The plugins failed to load properly. The error message given is

shown below.

exit

[Paul Sijpkes]

I uninstalled vagrant, restarted the machine and re-installed all plugins manually.  This seems to have resolved the issue.  I will keep this thread open until I now this is a stable solution.