diff --git a/core/Maps/DirectoryBrowser.php b/core/Maps/DirectoryBrowser.php
index 4b32bea3..bfb94d3c 100644
--- a/core/Maps/DirectoryBrowser.php
+++ b/core/Maps/DirectoryBrowser.php
@@ -512,7 +512,7 @@ class DirectoryBrowser implements ManialinkPageAnswerListener {
 						}
 
 						if ($filename !== null) {
-							if ($isUtf8 && strpos($filename, "utf-8''") === 0 && $filename = substr($filename, strlen("utf-8''"))) {
+							if ($isUtf8 && strpos(strtolower($filename), "utf-8''") === 0 && $filename = substr($filename, strlen("utf-8''"))) {
 								$filePath = $folderPath . FileUtil::getClearedFileName(rawurldecode($filename));
 							}
 							if (substr($filename, 0, 1) === '"' && substr($filename, -1, 1) === '"') {