diff --git a/apps/files/controller/apicontroller.php b/apps/files/controller/apicontroller.php
index 1ecd5294c6..ee54db6319 100644
--- a/apps/files/controller/apicontroller.php
+++ b/apps/files/controller/apicontroller.php
@@ -127,7 +127,7 @@ class ApiController extends Controller {
 	 *
 	 * @NoAdminRequired
 	 *
-	 * @param array|string $tagName tag name to filter by
+	 * @param string $tagName tag name to filter by
 	 * @return DataResponse
 	 */
 	public function getFilesByTag($tagName) {
diff --git a/apps/files/lib/activity.php b/apps/files/lib/activity.php
index 23e3f26e62..a941572ed1 100644
--- a/apps/files/lib/activity.php
+++ b/apps/files/lib/activity.php
@@ -166,7 +166,7 @@ class Activity implements IExtension {
 	 * @param string $text
 	 * @param IL10N $l
 	 * @param array $params
-	 * @return bool|string
+	 * @return string|false
 	 */
 	protected function translateLong($text, IL10N $l, array $params) {
 		switch ($text) {
@@ -198,7 +198,7 @@ class Activity implements IExtension {
 	 * @param string $text
 	 * @param IL10N $l
 	 * @param array $params
-	 * @return bool|string
+	 * @return string|false
 	 */
 	protected function translateShort($text, IL10N $l, array $params) {
 		switch ($text) {
diff --git a/apps/files/service/tagservice.php b/apps/files/service/tagservice.php
index 1999d97e1a..cf3f2bb786 100644
--- a/apps/files/service/tagservice.php
+++ b/apps/files/service/tagservice.php
@@ -91,7 +91,7 @@ class TagService {
 	/**
 	 * Get all files for the given tag
 	 *
-	 * @param array $tagName tag name to filter by
+	 * @param string $tagName tag name to filter by
 	 * @return FileInfo[] list of matching files
 	 * @throws \Exception if the tag does not exist
 	 */
diff --git a/apps/files_external/lib/config.php b/apps/files_external/lib/config.php
index fac3144553..b0b9db123c 100644
--- a/apps/files_external/lib/config.php
+++ b/apps/files_external/lib/config.php
@@ -243,6 +243,7 @@ class OC_Mount_Config {
 	 *
 	 * @param string $class backend class name
 	 * @param array $options backend configuration options
+	 * @param boolean $isPersonal
 	 * @return int see self::STATUS_*
 	 * @throws Exception
 	 */
@@ -362,11 +363,11 @@ class OC_Mount_Config {
 	private static function getSingleDependencyMessage(\OCP\IL10N $l, $module, $backend) {
 		switch (strtolower($module)) {
 			case 'curl':
-				return $l->t('<b>Note:</b> The cURL support in PHP is not enabled or installed. Mounting of %s is not possible. Please ask your system administrator to install it.', $backend);
+				return (string)$l->t('<b>Note:</b> The cURL support in PHP is not enabled or installed. Mounting of %s is not possible. Please ask your system administrator to install it.', $backend);
 			case 'ftp':
-				return $l->t('<b>Note:</b> The FTP support in PHP is not enabled or installed. Mounting of %s is not possible. Please ask your system administrator to install it.', $backend);
+				return (string)$l->t('<b>Note:</b> The FTP support in PHP is not enabled or installed. Mounting of %s is not possible. Please ask your system administrator to install it.', $backend);
 			default:
-				return $l->t('<b>Note:</b> "%s" is not installed. Mounting of %s is not possible. Please ask your system administrator to install it.', array($module, $backend));
+				return (string)$l->t('<b>Note:</b> "%s" is not installed. Mounting of %s is not possible. Please ask your system administrator to install it.', array($module, $backend));
 		}
 	}
 
diff --git a/apps/files_external/lib/config/configadapter.php b/apps/files_external/lib/config/configadapter.php
index 3a04512e8a..f9640d5337 100644
--- a/apps/files_external/lib/config/configadapter.php
+++ b/apps/files_external/lib/config/configadapter.php
@@ -32,7 +32,6 @@ use OCP\IUser;
 use OCA\Files_external\Service\UserStoragesService;
 use OCA\Files_External\Service\UserGlobalStoragesService;
 use OCA\Files_External\Lib\StorageConfig;
-use OCP\Files\StorageNotAvailableException;
 use OCA\Files_External\Lib\FailedStorage;
 
 /**
diff --git a/apps/files_external/lib/sftp.php b/apps/files_external/lib/sftp.php
index f8651727fd..bcf3143736 100644
--- a/apps/files_external/lib/sftp.php
+++ b/apps/files_external/lib/sftp.php
@@ -195,7 +195,7 @@ class SFTP extends \OC\Files\Storage\Common {
 	}
 
 	/**
-	 * @return bool|string
+	 * @return string|false
 	 */
 	private function hostKeysPath() {
 		try {