diff --git a/redirect.php b/redirect.php
index 23ad901..53769aa 100755
--- a/redirect.php
+++ b/redirect.php
@@ -165,7 +165,7 @@ function ParseSenderEmail($from) {
       $users[$data[0]] = $data[1];
     }
   }
-  if ($users[$email]) {
+  if (isset($users[$email])) {
     $project = $users[$email];
   }
   return $project;
@@ -182,7 +182,7 @@ function ParseSenderDomain($email) {
       $domains[$data[0]] = $data[1];
     }
   }
-  if($domains[$domain]) {
+  if(isset($domains[$domain])) {
     $project = $domains[$domain];
   }
   return $project;