diff --git a/composer.json b/composer.json
index 5564cb346..2edbaabb1 100644
--- a/composer.json
+++ b/composer.json
@@ -52,7 +52,6 @@
         ],
         "cs-check": "phpcs --colors -p",
         "cs-fix": "phpcbf --colors -p",
-        "stan": "phpstan analyze",
         "test": "phpunit --colors=always"
     }
 }
diff --git a/src/Console/Installer.php b/src/Console/Installer.php
index 847d9ded2..89aadda15 100644
--- a/src/Console/Installer.php
+++ b/src/Console/Installer.php
@@ -155,8 +155,7 @@ public static function setFolderPermissions(string $dir, IOInterface $io): void
         };
 
         $walker = function (string $dir) use (&$walker, $changePerms): void {
-            /** @phpstan-ignore-next-line */
-            $files = array_diff(scandir($dir), ['.', '..']);
+            $files = array_diff(scandir($dir) ?: [], ['.', '..']);
             foreach ($files as $file) {
                 $path = $dir . '/' . $file;
 
@@ -200,8 +199,12 @@ public static function setSecuritySaltInFile(string $dir, IOInterface $io, strin
     {
         $config = $dir . '/config/' . $file;
         $content = file_get_contents($config);
+        if ($content === false) {
+            $io->write('Config file not readable or not found: config/' . $file);
+
+            return;
+        }
 
-        /** @phpstan-ignore-next-line */
         $content = str_replace('__SALT__', $newKey, $content, $count);
 
         if ($count == 0) {
@@ -232,7 +235,12 @@ public static function setAppNameInFile(string $dir, IOInterface $io, string $ap
     {
         $config = $dir . '/config/' . $file;
         $content = file_get_contents($config);
-        /** @phpstan-ignore-next-line */
+        if ($content === false) {
+            $io->write('Config file not readable or not found: config/' . $file);
+
+            return;
+        }
+
         $content = str_replace('__APP_NAME__', $appName, $content, $count);
 
         if ($count == 0) {