diff --git a/src/FileMaker.php b/src/FileMaker.php
index dc65c5c..9984799 100644
--- a/src/FileMaker.php
+++ b/src/FileMaker.php
@@ -751,7 +751,7 @@ public function execute($params, $grammar = 'fmresultset')
 
         if ($this->getProperty('username')) {
             $auth = base64_encode(
-                utf8_decode($this->getProperty('username')) . ':' . utf8_decode($this->getProperty('password'))
+                $this->getProperty('username') . ':' . $this->getProperty('password')
             );
             $authHeader = 'Authorization: Basic ' . $auth;
             curl_setopt(