diff --git a/upload/system/library/mail.php b/upload/system/library/mail.php
index 3b5f2a63..65c6dc2f 100644
--- a/upload/system/library/mail.php
+++ b/upload/system/library/mail.php
@@ -95,7 +95,7 @@ public function send() {
 		if ($this->protocol != 'mail') {
 			$header .= 'To: <' . $to . '>' . $eol;
 			$header .= 'Subject: =?UTF-8?B?' . base64_encode($this->subject) . '?=' . $eol;
-			$header .= 'Message-ID: <' . base_convert(str_replace(['.', ' '], '', microtime()), 10, 36) . '.' . base_convert(bin2hex(openssl_random_pseudo_bytes(8)), 16, 36) . substr($this->from, strrpos($this->from, '@')) . '>' . PHP_EOL;
+			$header .= 'Message-ID: <' . base_convert(str_replace(['.', ' '], '', microtime()), 10, 36) . '.' . base_convert(bin2hex(openssl_random_pseudo_bytes(8)), 16, 36) . substr($this->from, strrpos($this->from, '@')) . '>' . $eol;
 		}
 
 		$header .= 'Date: ' . date('D, d M Y H:i:s O') . $eol;