diff --git a/apps/files_external/lib/Lib/Storage/SFTP.php b/apps/files_external/lib/Lib/Storage/SFTP.php
index 9d8c27dfa8d03..80b1472ce6664 100644
--- a/apps/files_external/lib/Lib/Storage/SFTP.php
+++ b/apps/files_external/lib/Lib/Storage/SFTP.php
@@ -506,7 +506,7 @@ public function writeStream(string $path, $stream, int $size = null): int {
 			$stream = CountWrapper::wrap($stream, function (int $writtenSize) use (&$size) {
 				$size = $writtenSize;
 			});
-			if (!$stream) {
+			if (!is_resource($stream)) {
 				throw new \Exception("Failed to wrap stream");
 			}
 		}