diff --git a/lib/Froxlor/Install/Install/Core.php b/lib/Froxlor/Install/Install/Core.php
index c6267825..3f4d89e1 100644
--- a/lib/Froxlor/Install/Install/Core.php
+++ b/lib/Froxlor/Install/Install/Core.php
@@ -352,7 +352,7 @@ class Core
 
 			$pdo->query($froxlorSQL);
 		} catch (PDOException $e) {
-			throw new Exception('failed to import data!', 0, $e);
+			throw new Exception('failed to import data!' . $e->getMessage(), 0, $e);
 		}
 	}
 
diff --git a/lib/Froxlor/PhpHelper.php b/lib/Froxlor/PhpHelper.php
index 87d98a6f..d45a6642 100644
--- a/lib/Froxlor/PhpHelper.php
+++ b/lib/Froxlor/PhpHelper.php
@@ -468,7 +468,7 @@ class PhpHelper
 		}
 	}
 
-	private static function sortListByGivenKey($a, $b)
+	private static function sortListByGivenKey($a, $b): int
 	{
 		if (self::$sort_type == SORT_NATURAL) {
 			return strnatcasecmp($a[self::$sort_key], $b[self::$sort_key]);
@@ -480,10 +480,11 @@ class PhpHelper
 	 * Generate php file from array.
 	 *
 	 * @param array $array
+	 * @param string|null $comment
 	 * @param bool $asReturn
 	 * @return string
 	 */
-	public static function parseArrayToPhpFile(array $array, string $comment = null, $asReturn = false): string
+	public static function parseArrayToPhpFile(array $array, string $comment = null, bool $asReturn = false): string
 	{
 		$str = sprintf("<?php\n// %s\n\n", $comment ?? 'autogenerated froxlor file');