diff --git a/Business/Marketing/NetPromoterScore.php b/Business/Marketing/NetPromoterScore.php
index d8133d4a9..856f79a44 100644
--- a/Business/Marketing/NetPromoterScore.php
+++ b/Business/Marketing/NetPromoterScore.php
@@ -96,7 +96,7 @@ final class NetPromoterScore
         $count = 0;
         foreach ($this->scores as $score) {
             if ($score < 7) {
-                $count++;
+                ++$count;
             }
         }
 
@@ -117,7 +117,7 @@ final class NetPromoterScore
         $count = 0;
         foreach ($this->scores as $score) {
             if ($score > 6 && $score < 9) {
-                $count++;
+                ++$count;
             }
         }
 
@@ -138,7 +138,7 @@ final class NetPromoterScore
         $count = 0;
         foreach ($this->scores as $score) {
             if ($score > 8) {
-                $count++;
+                ++$count;
             }
         }
 
diff --git a/Math/Number/Numbers.php b/Math/Number/Numbers.php
index db0387040..b20c0b42c 100644
--- a/Math/Number/Numbers.php
+++ b/Math/Number/Numbers.php
@@ -114,7 +114,7 @@ final class Numbers
             if ($n & 1 == 1) {
                 break;
             } else {
-                $count++;
+                ++$count;
                 $n = $n >> 1;
             }
         }
diff --git a/System/File/FileUtils.php b/System/File/FileUtils.php
index 8179de921..79dcfb965 100644
--- a/System/File/FileUtils.php
+++ b/System/File/FileUtils.php
@@ -130,10 +130,11 @@ final class FileUtils
      */
     public static function changeFileEncoding(string $file, string $encoding) : void
     {
-        $content = \file_get_contents($file);
+        $content  = \file_get_contents($file);
+        $detected = \mb_detect_encoding($content);
 
-        if ($content !== false && \preg_match('!!u', $content)) {
-            \file_put_contents($file, \mb_convert_encoding($content, 'UTF-8', \mb_list_encodings()));
+        if ($content !== false) {
+            \file_put_contents($file, \mb_convert_encoding($content, $encoding, $detected === false ? \mb_list_encodings() : $detected));
         }
     }