diff --git a/console-ui/public/portal/index.html b/console-ui/public/portal/index.html
index 2e7f114..febd877 100644
--- a/console-ui/public/portal/index.html
+++ b/console-ui/public/portal/index.html
@@ -200,6 +200,8 @@
       <input type="password" id="fs-password2" class="txt" placeholder="再輸入一次密碼" autocomplete="new-password" style="padding:15px 16px;font-size:17px;border-radius:11px">
       <button class="btn" id="fs-submit" style="margin-top:6px;padding:15px;font-size:17px;letter-spacing:.12em">建立帳號並進入</button>
       <div id="fs-status" class="err" style="font-size:14px;min-height:1.2em"></div>
+      <!-- leo 07-25 實撞：已設定過(409)時這頁是死路——必須有回登入的路 -->
+      <button class="btn3" id="fs-tologin" style="padding:9px 16px;font-size:14px;border-radius:999px;align-self:center;cursor:pointer">已經有帳號？改用登入</button>
     </div>
     <div style="font-size:13.5px;color:rgba(var(--ink-rgb),.4);line-height:1.7">這組帳密就是之後登入知識庫用的，只需要設定這一次。</div>
   </div>
@@ -680,6 +682,10 @@ function taipeiMonthDay(ms) { var d = new Date(ms + TAIPEI_OFFSET_MS); return {
   //    四發全是既有端點，一顆按鈕做完；用戶感受＝「建一組帳密就進來了」。
   $('fs-submit').addEventListener('click', doFirstSetup);
   $('fs-password2').addEventListener('keydown', function (ev) { if (ev.key === 'Enter') doFirstSetup(); });
+  $('fs-tologin').addEventListener('click', function () {
+    $('v-firstsetup').classList.remove('on');
+    $('v-login').classList.add('on');
+  });
   function doFirstSetup() {
     var email = $('fs-email').value.trim();
     var pw = $('fs-password').value;
@@ -696,6 +702,15 @@ function taipeiMonthDay(ms) { var d = new Date(ms + TAIPEI_OFFSET_MS); return {
     };
     post('/console/setup', { email: email, password: pw })
       .then(function (x) {
+        // 已設定過（409）＝這實例其實有人建過了——自動帶去登入，別把用戶困在死路（leo 實撞）
+        if (x.status === 409) {
+          $('fs-submit').disabled = false;
+          $('v-firstsetup').classList.remove('on');
+          $('v-login').classList.add('on');
+          $('login-email').value = email;
+          $('login-status').textContent = '這個知識庫已經設定過帳號了，直接登入即可。';
+          throw { handled: true };
+        }
         if (!x.ok || !x.d.session_token) throw new Error(x.d.error || '設定沒有成功，請再試一次');
         var ownerTok = x.d.session_token;
         return post('/portal/admin/bootstrap', { email: email, password: pw, display_name: email.split('@')[0] }, { Authorization: 'Bearer ' + ownerTok })
@@ -724,6 +739,7 @@ function taipeiMonthDay(ms) { var d = new Date(ms + TAIPEI_OFFSET_MS); return {
         boot();
       })
       .catch(function (e) {
+        if (e && e.handled) return; // 409 已自動切登入，不再顯示錯誤
         $('fs-submit').disabled = false;
         st.textContent = (e && e.message) || friendlyErr(e);
       });