I have Contact 7 on my Twenty Eleven Template Child.
Form was sending emails prior to upgrade to latest ver of Contact 7 (18.104.22.168), then afterwards I got he spinning arrows after hitting submit. Did not and still do not see any notification that form was submitted OK; it just clears.
Found recommended fix for spinning arrows:
define( 'WPCF7_LOAD_JS', true);
define( 'WPCF7_LOAD_JS', false );
and spinning went away but still not sending emails.
My host is Fluid Hosting.