diff --git a/test/PHPMailerTest.php b/test/PHPMailerTest.php
index d7ad1c8a..91804e34 100644
--- a/test/PHPMailerTest.php
+++ b/test/PHPMailerTest.php
@@ -3031,16 +3031,6 @@ EOT;
         $this->assertFalse($this->Mail->addAddress('mehome.com'));
     }
 
-    /**
-     * Check IDN test environment
-     * @test
-     */
-    public function check_idn_test_env()
-    {
-        $this->assertTrue(function_exists('idn_to_ascii'), 'idn_to_ascii function missing');
-        $this->assertTrue(function_exists('mb_convert_encoding'), 'mb_convert_encoding function missing');
-    }
-
     /**
      * Test RFC822 address list parsing using PHPMailer's parser.
      * @test