diff --git a/tests/lib/cache/file.php b/tests/lib/cache/file.php
index 6db5acdf13..7aa969df02 100644
--- a/tests/lib/cache/file.php
+++ b/tests/lib/cache/file.php
@@ -63,8 +63,9 @@ class FileCache extends \Test_Cache {
 		$storage = new \OC\Files\Storage\Temporary(array());
 		\OC\Files\Filesystem::mount($storage,array(),'/');
 		$datadir = str_replace('local::', '', $storage->getId());
-		$this->datadir = \OC_Config::getValue('cachedirectory', \OC::$SERVERROOT.'/data/cache');
-		\OC_Config::setValue('cachedirectory', $datadir);
+		$config = \OC::$server->getConfig();
+		$this->datadir = $config->getSystemValue('cachedirectory', \OC::$SERVERROOT.'/data/cache');
+		$config->setSystemValue('cachedirectory', $datadir);
 
 		\OC_User::clearBackends();
 		\OC_User::useBackend(new \Test\Util\User\Dummy());
@@ -89,7 +90,7 @@ class FileCache extends \Test_Cache {
 		$this->instance->remove('hack', 'hack');
 
 		\OC_User::setUserId($this->user);
-		\OC_Config::setValue('cachedirectory', $this->datadir);
+		\OC::$server->getConfig()->setSystemValue('cachedirectory', $this->datadir);
 
 		// Restore the original mount point
 		\OC\Files\Filesystem::clearMounts();
diff --git a/tests/lib/files/etagtest.php b/tests/lib/files/etagtest.php
index 7fbeae8882..c214a3d4da 100644
--- a/tests/lib/files/etagtest.php
+++ b/tests/lib/files/etagtest.php
@@ -37,16 +37,17 @@ class EtagTest extends \Test\TestCase {
 		\OCP\Share::registerBackend('file', 'OC_Share_Backend_File');
 		\OCP\Share::registerBackend('folder', 'OC_Share_Backend_Folder', 'file');
 
-		$this->datadir = \OC_Config::getValue('datadirectory');
+		$config = \OC::$server->getConfig();
+		$this->datadir = $config->getSystemValue('datadirectory');
 		$this->tmpDir = \OC_Helper::tmpFolder();
-		\OC_Config::setValue('datadirectory', $this->tmpDir);
+		$config->setSystemValue('datadirectory', $this->tmpDir);
 
 		$this->userBackend = new \Test\Util\User\Dummy();
 		\OC_User::useBackend($this->userBackend);
 	}
 
 	protected function tearDown() {
-		\OC_Config::setValue('datadirectory', $this->datadir);
+		\OC::$server->getConfig()->setSystemValue('datadirectory', $this->datadir);
 
 		$this->logout();
 		parent::tearDown();