diff --git a/desktop/app.js b/desktop/app.js
index 7ccea66..cb92944 100644
--- a/desktop/app.js
+++ b/desktop/app.js
@@ -1,7 +1,9 @@
 import { app, dialog, nativeImage, shell, Menu } from 'electron';
+import fs from 'fs/promises';
+import fsSync from 'fs';
 import path from 'path';
 import { fileURLToPath } from 'url';
-import { loadDesktopConfig, saveDesktopConfig, resetDesktopConfig } from './config.js';
+import { loadDesktopConfig, saveDesktopConfig, resetDesktopConfig, getDefaultDesktopConfig } from './config.js';
 import { resolveLocale, getMessages } from './i18n.js';
 import { getFreePort, isPortAvailable } from './ports.js';
 import { getServerStatus, startServerWithConfig, stopServerInstance } from './server.js';
@@ -24,6 +26,7 @@ let messages = getMessages(locale);
 let tray = null;
 const repoUrl = 'https://github.com/xxnuo/MTranServer';
 let portCheckPromise = null;
+let desktopLogPath = null;
 
 function getLocalHost(host) {
   if (!host || host === '0.0.0.0') return '127.0.0.1';
@@ -69,6 +72,17 @@ function updateTray() {
   });
 }
 
+async function logDesktop(message, error) {
+  if (!desktopLogPath) return;
+  const timestamp = new Date().toISOString();
+  const details = error ? ` ${error.stack || error.message || error}` : '';
+  try {
+    await fs.appendFile(desktopLogPath, `[${timestamp}] ${message}${details}\n`, 'utf8');
+  } catch {
+    return;
+  }
+}
+
 async function ensurePortAvailable() {
   if (portCheckPromise) return portCheckPromise;
   portCheckPromise = (async () => {
@@ -76,6 +90,7 @@ async function ensurePortAvailable() {
     const available = await isPortAvailable(desktopConfig.server.port, host);
     if (available) return true;
 
+    await logDesktop(`port in use ${desktopConfig.server.port}`);
     const result = await dialog.showMessageBox({
       type: 'warning',
       buttons: [messages.portInUseUseRandom, messages.portInUseQuit],
@@ -87,10 +102,12 @@ async function ensurePortAvailable() {
 
     if (result.response === 0) {
       const newPort = await getFreePort();
+      await logDesktop(`use random port ${newPort}`);
       desktopConfig.server.port = newPort;
       desktopConfig = await saveDesktopConfig(desktopConfig);
       return true;
     }
+    await logDesktop('quit after port in use');
     await quitApp();
     return false;
   })();
@@ -105,9 +122,12 @@ async function startServer() {
   const ok = await ensurePortAvailable();
   if (!ok) return false;
   try {
+    await logDesktop('starting server');
     await startServerWithConfig(desktopConfig.server);
+    await logDesktop('server started');
     return true;
-  } catch {
+  } catch (error) {
+    await logDesktop('server start failed', error);
     dialog.showMessageBox({
       type: 'error',
       message: messages.serverStartFailed,
@@ -119,7 +139,9 @@ async function startServer() {
 
 async function restartServer() {
   try {
+    await logDesktop('restarting server');
     await stopServerInstance();
+    await ensureWritableDirs();
     const ok = await startServer();
     if (!ok) return false;
     updateWindowUrls({
@@ -138,6 +160,7 @@ async function restartServer() {
 }
 
 async function quitApp() {
+  await logDesktop('quit app');
   app.isQuitting = true;
   await stopServerInstance();
   app.quit();
@@ -149,6 +172,40 @@ function updateLocale(nextLocale) {
   updateTray();
 }
 
+async function ensureWritableDirs() {
+  const defaults = getDefaultDesktopConfig();
+  const updates = {};
+  const targets = [
+    ['modelDir', defaults.server.modelDir],
+    ['logDir', defaults.server.logDir],
+    ['configDir', defaults.server.configDir]
+  ];
+
+  for (const [key, fallback] of targets) {
+    const target = desktopConfig.server[key];
+    if (!target) {
+      updates[key] = fallback;
+      continue;
+    }
+    try {
+      await fs.mkdir(target, { recursive: true });
+      await fs.access(target, fsSync.constants.W_OK);
+    } catch {
+      updates[key] = fallback;
+    }
+  }
+
+  if (Object.keys(updates).length > 0) {
+    desktopConfig = await saveDesktopConfig({
+      ...desktopConfig,
+      server: {
+        ...desktopConfig.server,
+        ...updates
+      }
+    });
+  }
+}
+
 function getLoadingUrl() {
   const html = `
   <!doctype html>
@@ -185,6 +242,10 @@ export async function startDesktop() {
   Menu.setApplicationMenu(null);
   desktopConfig = await loadDesktopConfig();
   updateLocale(desktopConfig.locale);
+  desktopLogPath = path.join(desktopConfig.server.configDir, 'desktop.log');
+  await fs.mkdir(desktopConfig.server.configDir, { recursive: true });
+  await logDesktop('desktop starting');
+  await ensureWritableDirs();
 
   const preloadPath = path.join(__dirname, 'preload.cjs');
   const loadingUrl = getLoadingUrl();
diff --git a/package.json b/package.json
index 4e7c7cc..b06b743 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
     "bump": "bun scripts/bump.ts",
     "electron": "bun run build:lib && electron ./electron-main.js",
     "electron:dev": "bun run scripts/electron-dev.ts",
-    "electron:build": "bun run build:lib && electron-builder",
+    "electron:build": "bun run scripts/electron-build.ts",
     "electron:build:all": "bun run build:lib && electron-builder -mwl",
     "prepublishOnly": "bun scripts/build.ts --lib",
     "push": "npm publish --registry=https://registry.npmjs.org",
@@ -58,6 +58,7 @@
     "typescript": "^5.9.3"
   },
   "dependencies": {
+    "ee-first": "^1.1.1",
     "express": "^5.2.1",
     "express-validator": "^7.3.1",
     "fzstd": "^0.1.1",
@@ -71,15 +72,23 @@
   "build": {
     "appId": "com.github.xxnuo.mtranserver",
     "productName": "MTranServer",
+    "executableName": "mtranserver",
     "copyright": "Copyright © 2025",
     "extraMetadata": {
       "main": "electron-main.js"
     },
+    "asar": true,
+    "asarUnpack": [
+      "dist/mtranserver*",
+      "dist/*.exe"
+    ],
     "artifactName": "mtranserver-desktop-${version}-${os}-${arch}.${ext}",
     "files": [
       "desktop/**/*",
       "electron-main.js",
       "dist/**/*",
+      "!dist/mtranserver*",
+      "!dist/*.exe",
       "images/**/*",
       "package.json",
       "node_modules/**/*"
diff --git a/scripts/electron-build.ts b/scripts/electron-build.ts
new file mode 100644
index 0000000..5339615
--- /dev/null
+++ b/scripts/electron-build.ts
@@ -0,0 +1,45 @@
+import { spawn } from 'child_process'
+import fs from 'fs'
+import path from 'path'
+
+function run(command: string, args: string[]) {
+  return new Promise<void>((resolve, reject) => {
+    const proc = spawn(command, args, { stdio: 'inherit', env: process.env })
+    proc.on('exit', (code) => {
+      if (code === 0) resolve()
+      else reject(new Error(`exit ${code}`))
+    })
+  })
+}
+
+async function main() {
+  const bunBin = process.execPath
+  await run(bunBin, ['run', 'build:lib'])
+
+  const distDir = path.join(process.cwd(), 'dist')
+  if (fs.existsSync(distDir)) {
+    for (const entry of fs.readdirSync(distDir)) {
+      if (entry.startsWith('mtranserver') || entry.endsWith('.exe')) {
+        try {
+          fs.rmSync(path.join(distDir, entry), { recursive: true, force: true })
+        } catch {
+          continue
+        }
+      }
+    }
+  }
+
+  const platform = process.platform
+  const builderArgs = ['node_modules/.bin/electron-builder']
+  if (platform === 'linux') {
+    builderArgs.push('--linux', 'AppImage')
+  } else if (platform === 'darwin') {
+    builderArgs.push('--mac')
+  } else if (platform === 'win32') {
+    builderArgs.push('--win')
+  }
+
+  await run(bunBin, builderArgs)
+}
+
+main().catch(() => process.exit(1))