diff --git a/phpBB/phpbb/storage/adapter/local.php b/phpBB/phpbb/storage/adapter/local.php
index 6471194090..94990a6bf7 100644
--- a/phpBB/phpbb/storage/adapter/local.php
+++ b/phpBB/phpbb/storage/adapter/local.php
@@ -428,9 +428,16 @@ class local implements adapter_interface, stream_interface
 	 */
 	public function free_space()
 	{
-		$free_space = @disk_free_space($this->root_path);
+		if (function_exists('disk_free_space'))
+		{
+			$free_space = @disk_free_space($this->root_path);
 
-		if ($free_space === false)
+			if ($free_space === false)
+			{
+				throw new exception('STORAGE_CANNOT_GET_FREE_SPACE');
+			}
+		}
+		else
 		{
 			throw new exception('STORAGE_CANNOT_GET_FREE_SPACE');
 		}
diff --git a/tests/attachment/upload_test.php b/tests/attachment/upload_test.php
index 47edd102c9..6e47ef35ee 100644
--- a/tests/attachment/upload_test.php
+++ b/tests/attachment/upload_test.php
@@ -85,6 +85,7 @@ class phpbb_attachment_upload_test extends \phpbb_database_test_case
 			'img_create_thumbnail'	=> true,
 		));
 		$config = $this->config;
+		$this->phpbb_root_path = $phpbb_root_path;
 		$this->db = $this->new_dbal();
 		$this->cache = new \phpbb\cache\service(new \phpbb\cache\driver\dummy(), $this->config, $this->db, $phpbb_root_path, $phpEx);
 		$this->request = $this->createMock('\phpbb\request\request');