diff --git a/DataStorage/Database/GrammarAbstract.php b/DataStorage/Database/GrammarAbstract.php
index 7083820e1..7f03873b9 100644
--- a/DataStorage/Database/GrammarAbstract.php
+++ b/DataStorage/Database/GrammarAbstract.php
@@ -269,9 +269,9 @@ abstract class GrammarAbstract
      */
     protected function compileSystem(string $system, string $prefix = '') : string
     {
-        // todo: this is a bad way to handle select \count(*) which doesn't need a prefix. Maybe remove prefixes in total?
         $identifier = $this->systemIdentifier;
 
+        // todo: this is a bad way to handle select \count(*) which doesn't need a prefix. Maybe remove prefixes in total?
         foreach ($this->specialKeywords as $keyword) {
             if (\strrpos($system, $keyword, -\strlen($system)) !== false) {
                 $prefix     = '';
@@ -279,7 +279,6 @@ abstract class GrammarAbstract
             }
         }
 
-        // todo: move remaining * test also here not just if .* but also if * (should be done in else?)
         if (\count($split = \explode('.', $system)) > 1) {
             $fullSystem = '';
 
diff --git a/DataStorage/Session/HttpSession.php b/DataStorage/Session/HttpSession.php
index 6230c4119..f19603e8e 100644
--- a/DataStorage/Session/HttpSession.php
+++ b/DataStorage/Session/HttpSession.php
@@ -37,7 +37,7 @@ class HttpSession implements SessionInterface
      * @var bool
      * @since 1.0.0
      */
-    private static $isLocked = false;
+    private $isLocked = false;
 
     /**
      * Raw session data.
@@ -76,7 +76,7 @@ class HttpSession implements SessionInterface
      */
     public function __construct(int $liftetime = 3600, $sid = false, int $inactivityInterval = 0)
     {
-        if (self::$isLocked) {
+        if ($this->isLocked) {
             throw new LockException('HttpSession');
         }
 
@@ -153,7 +153,7 @@ class HttpSession implements SessionInterface
      */
     public function lock() : void
     {
-        self::$isLocked = true;
+        $this->isLocked = true;
     }
 
     /**
@@ -163,9 +163,9 @@ class HttpSession implements SessionInterface
      *
      * @since  1.0.0
      */
-    public static function isLocked() : bool
+    public function isLocked() : bool
     {
-        return self::$isLocked;
+        return $this->isLocked;
     }
 
     /**
@@ -173,7 +173,7 @@ class HttpSession implements SessionInterface
      */
     public function save() : void
     {
-        if (!self::$isLocked) {
+        if (!$this->isLocked) {
             $_SESSION = $this->sessionData;
             \session_write_close();
         }
diff --git a/Event/EventManager.php b/Event/EventManager.php
index 936a0891e..0a77eba49 100644
--- a/Event/EventManager.php
+++ b/Event/EventManager.php
@@ -42,15 +42,6 @@ final class EventManager
      */
     private $callbacks = [];
 
-    /**
-     * Constructor.
-     *
-     * @since  1.0.0
-     */
-    public function __construct()
-    {
-    }
-
     /**
      * Attach new event
      *
@@ -96,7 +87,6 @@ final class EventManager
         }
 
         if (!$this->hasOutstanding($group)) {
-            // todo if it is route then call dispatcher?
             $this->callbacks[$group]['func']($data);
 
             if ($this->callbacks[$group]['remove']) {
diff --git a/Log/FileLogger.php b/Log/FileLogger.php
index 12b52db0c..31edbdc71 100644
--- a/Log/FileLogger.php
+++ b/Log/FileLogger.php
@@ -98,11 +98,11 @@ final class FileLogger implements LoggerInterface
      */
     public function __construct(string $lpath, bool $verbose = false)
     {
-        $path          = \realpath($lpath);
+        $path          = \realpath(empty($lpath) ? __DIR__ . '/../../' : $lpath);
         $this->verbose = $verbose;
 
         if (\is_dir($lpath) || \strpos($lpath, '.') === false) {
-            $path = $lpath . '/' . \date('Y-m-d') . '.log';
+            $path = \rtrim($lpath, '/') . '/' . \date('Y-m-d') . '.log';
         } else {
             $path = $lpath;
         }
diff --git a/Message/Console/Response.php b/Message/Console/Response.php
index 10effadb6..82255efc0 100644
--- a/Message/Console/Response.php
+++ b/Message/Console/Response.php
@@ -20,6 +20,8 @@ use phpOMS\Message\ResponseAbstract;
 use phpOMS\System\MimeType;
 use phpOMS\Views\View;
 use phpOMS\Message\Http\RequestStatusCode;
+use phpOMS\Log\FileLogger;
+use phpOMS\Log\LogLevel;
 
 /**
  * Response class.
@@ -164,8 +166,15 @@ final class Response extends ResponseAbstract implements RenderableInterface
                 }
             }
         } catch (\Exception $e) {
-            // todo: handle exception
-            // need to to try catch for logging. otherwise the json_encode in the logger will have a problem with this
+            FileLogger::getInstance('', false)
+                ->error(
+                    FileLogger::MSG_FULL, [
+                        'message' => $e->getMessage(),
+                        'line'    => __LINE__,
+                        'file'    => Response::class,
+                    ]
+                );
+
             $result = [];
         } finally {
             return $result;
diff --git a/Message/HeaderAbstract.php b/Message/HeaderAbstract.php
index 7514da230..03ee5de6c 100644
--- a/Message/HeaderAbstract.php
+++ b/Message/HeaderAbstract.php
@@ -32,7 +32,7 @@ abstract class HeaderAbstract
      * @var bool
      * @since 1.0.0
      */
-    protected static $isLocked = false;
+    protected $isLocked = false;
 
     /**
      * Localization.
@@ -75,10 +75,9 @@ abstract class HeaderAbstract
      *
      * @since  1.0.0
      */
-    public static function lock() : void
+    public function lock() : void
     {
-        // todo: maybe pass session as member and make lock not static
-        self::$isLocked = true;
+        $this->isLocked = true;
     }
 
     /**
@@ -88,9 +87,9 @@ abstract class HeaderAbstract
      *
      * @since  1.0.0
      */
-    public static function isLocked() : bool
+    public function isLocked() : bool
     {
-        return self::$isLocked;
+        return $this->isLocked;
     }
 
     /**
diff --git a/Message/Http/Header.php b/Message/Http/Header.php
index 078836cec..a74689683 100644
--- a/Message/Http/Header.php
+++ b/Message/Http/Header.php
@@ -62,7 +62,7 @@ final class Header extends HeaderAbstract
      */
     public function set(string $key, string $header, bool $overwrite = false) : bool
     {
-        if (self::$isLocked) {
+        if ($this->isLocked) {
             return false;
         }
 
@@ -167,7 +167,7 @@ final class Header extends HeaderAbstract
      */
     public function remove($key) : bool
     {
-        if (self::$isLocked) {
+        if ($this->isLocked) {
             return false;
         }
 
@@ -228,7 +228,7 @@ final class Header extends HeaderAbstract
      */
     public function push() : void
     {
-        if (self::$isLocked) {
+        if ($this->isLocked) {
             throw new \Exception('Already locked');
         }
 
diff --git a/Message/Http/Response.php b/Message/Http/Response.php
index c536881d7..cdce20582 100644
--- a/Message/Http/Response.php
+++ b/Message/Http/Response.php
@@ -19,6 +19,7 @@ use phpOMS\Localization\Localization;
 use phpOMS\Message\ResponseAbstract;
 use phpOMS\System\MimeType;
 use phpOMS\Views\View;
+use phpOMS\Log\FileLogger;
 
 /**
  * Response class.
@@ -184,8 +185,15 @@ final class Response extends ResponseAbstract implements RenderableInterface
                 }
             }
         } catch (\Exception $e) {
-            // todo: handle exception
-            // need to to try catch for logging. otherwise the json_encode in the logger will have a problem with this
+            FileLogger::getInstance('', false)
+                ->error(
+                    FileLogger::MSG_FULL, [
+                        'message' => $e->getMessage(),
+                        'line'    => __LINE__,
+                        'file'    => Response::class,
+                    ]
+                );
+
             $result = [];
         } finally {
             return $result;
diff --git a/Stdlib/Map/MultiMap.php b/Stdlib/Map/MultiMap.php
index d480147e7..f7560464e 100644
--- a/Stdlib/Map/MultiMap.php
+++ b/Stdlib/Map/MultiMap.php
@@ -107,7 +107,7 @@ class MultiMap implements \Countable
         }
 
         // todo: is this really required???? - i don't think so!
-        $this->garbageCollect();
+        //$this->garbageCollect();
 
         return $inserted;
     }
diff --git a/Utils/StringCompare.php b/Utils/StringCompare.php
index ecd2c0bbb..3bc550542 100644
--- a/Utils/StringCompare.php
+++ b/Utils/StringCompare.php
@@ -107,7 +107,6 @@ final class StringCompare
         }
 
         foreach ($words1 as $word1) {
-            // todo: is this correct?
             $best = \strlen($s2);
 
             foreach ($words2 as $word2) {
@@ -122,8 +121,7 @@ final class StringCompare
                 }
             }
 
-            // todo: is this correct?
-            $total += $total + $best;
+            $total += $best;
         }
 
         return $total;
diff --git a/tests/DataStorage/Session/HttpSessionTest.php b/tests/DataStorage/Session/HttpSessionTest.php
index 9514b5e25..57892889a 100644
--- a/tests/DataStorage/Session/HttpSessionTest.php
+++ b/tests/DataStorage/Session/HttpSessionTest.php
@@ -21,7 +21,7 @@ class HttpSessionTest extends \PHPUnit\Framework\TestCase
     {
         $session = new HttpSession();
         self::assertEquals(null, $session->get('key'));
-        self::assertFalse(HttpSession::isLocked());
+        self::assertFalse($session->isLocked());
     }
 
     public function testGetSet()
diff --git a/tests/Message/Http/HeaderTest.php b/tests/Message/Http/HeaderTest.php
index 7d14ce65c..46121fc91 100644
--- a/tests/Message/Http/HeaderTest.php
+++ b/tests/Message/Http/HeaderTest.php
@@ -70,8 +70,8 @@ class HeaderTest extends \PHPUnit\Framework\TestCase
     public function testLockedHeaderSet()
     {
         $header = new Header();
-        Header::lock();
-        self::assertTrue(Header::isLocked());
+        $header->lock();
+        self::assertTrue($header->isLocked());
         self::assertFalse($header->set('key', 'value'));
 
         TestUtils::setMember('phpOMS\Message\Http\Header', 'isLocked', false);
@@ -80,8 +80,8 @@ class HeaderTest extends \PHPUnit\Framework\TestCase
     public function testLockedHeaderRemove()
     {
         $header = new Header();
-        Header::lock();
-        self::assertTrue(Header::isLocked());
+        $header->lock();
+        self::assertTrue($header->isLocked());
         self::assertFalse($header->remove('key'));
 
         TestUtils::setMember('phpOMS\Message\Http\Header', 'isLocked', false);