diff --git a/mu-plugins/10up-plugin/includes/classes/ModuleInitialization.php b/mu-plugins/10up-plugin/includes/classes/ModuleInitialization.php
index b5a8ea87..bf22ec64 100644
--- a/mu-plugins/10up-plugin/includes/classes/ModuleInitialization.php
+++ b/mu-plugins/10up-plugin/includes/classes/ModuleInitialization.php
@@ -56,7 +56,9 @@ private function __construct() {
 	 * @return array
 	 */
 	protected function get_classes() {
-		return ClassFinder::getClassesInNamespace( 'TenUpPlugin', ClassFinder::RECURSIVE_MODE );
+		$class_finder = new ClassFinder();
+		$class_finder::setAppRoot( TENUP_PLUGIN_PATH );
+		return $class_finder::getClassesInNamespace( 'TenUpPlugin', ClassFinder::RECURSIVE_MODE );
 	}
 
 	/**
diff --git a/themes/10up-theme/includes/classes/ModuleInitialization.php b/themes/10up-theme/includes/classes/ModuleInitialization.php
index a80628ba..ce71761f 100644
--- a/themes/10up-theme/includes/classes/ModuleInitialization.php
+++ b/themes/10up-theme/includes/classes/ModuleInitialization.php
@@ -56,7 +56,9 @@ private function __construct() {
 	 * @return array
 	 */
 	protected function get_classes() {
-		return ClassFinder::getClassesInNamespace( 'TenUpTheme', ClassFinder::RECURSIVE_MODE );
+		$class_finder = new ClassFinder();
+		$class_finder::setAppRoot( TENUP_THEME_PATH );
+		return $class_finder::getClassesInNamespace( 'TenUpTheme', ClassFinder::RECURSIVE_MODE );
 	}
 
 	/**