diff --git a/lib/tasks/configuration.rake b/lib/tasks/configuration.rake
index 9e720988..f1203557 100644
--- a/lib/tasks/configuration.rake
+++ b/lib/tasks/configuration.rake
@@ -44,8 +44,11 @@ def test_smtp
     smtp.enable_starttls_auto if smtp.respond_to?(:enable_starttls_auto)
   end
 
-  smtp.start(ENV['SMTP_DOMAIN'], ENV['SMTP_USERNAME'], ENV['SMTP_PASSWORD'],
-    ENV['SMTP_AUTH']) do |s|
+  user = ENV['SMTP_USERNAME'].presence || nil
+  password = ENV['SMTP_PASSWORD'].presence || nil
+  authtype = ENV['SMTP_AUTH'].present? && ENV['SMTP_AUTH'] != "none" ? ENV['SMTP_AUTH'] : nil
+
+  smtp.start(ENV['SMTP_DOMAIN'], user, password, authtype) do |s|
     s.sendmail('test', ENV['SMTP_USERNAME'], 'notifications@example.com')
   end
 rescue => e