diff --git a/inc/HTTPAuthSession.php b/inc/HTTPAuthSession.php
index c2768b55..e5ec3cbb 100644
--- a/inc/HTTPAuthSession.php
+++ b/inc/HTTPAuthSession.php
@@ -458,7 +458,7 @@ class HTTPAuthSession {
 
     $salt = $cache->get($cache_ns, 'salt');
 
-    if (isset($salt)) {
+    if (isset($salt) && $salt != '') {
       $sha1_sent = session_salted_sha1($password, $salt);
       $cached_credentials = $cache->get($cache_ns, $sha1_sent);