diff --git a/packages/adapter-electron/functions/setupHandler.js b/packages/adapter-electron/functions/setupHandler.js
index 4cc008f..669f597 100644
--- a/packages/adapter-electron/functions/setupHandler.js
+++ b/packages/adapter-electron/functions/setupHandler.js
@@ -52,7 +52,7 @@ export function getPreloadPath() {
   let preloadPath = path.resolve(path.join(__dirname, 'PRELOAD'))
 
   if (isDev) {
-    preloadPath = path.resolve(path.join(__dirname, '..', 'preload', 'index.js'))
+    preloadPath = path.resolve(path.join(__dirname, '..', 'preload', 'index.cjs'))
   }
 
   return preloadPath;
@@ -418,4 +418,4 @@ export const isSafePath = (base, target) => {
     reportError(new Error(`Unsafe path detected: base=${base}, target=${target}, relative=${relative}`), 'Path traversal attempt');
   }
   return safe;
-}; 
\ No newline at end of file
+};