diff --git a/LibreNMS/Validations/Mail.php b/LibreNMS/Validations/Mail.php
index 240b6c98bd..f36a4dd158 100644
--- a/LibreNMS/Validations/Mail.php
+++ b/LibreNMS/Validations/Mail.php
@@ -46,7 +46,7 @@ class Mail implements ValidationGroup
                 $validator->fail('default_mail config option needs to be specified to test email');
                 $run_test = 0;
             } elseif (Config::get('email_backend') == 'sendmail') {
-                if (Config::has('email_sendmail_path')) {
+                if (!Config::has('email_sendmail_path')) {
                     $validator->fail("You have selected sendmail but not configured email_sendmail_path");
                     $run_test = 0;
                 } elseif (!file_exists(Config::get('email_sendmail_path'))) {