diff --git a/README.md b/README.md
index b6bbf031..0c9ee16f 100644
--- a/README.md
+++ b/README.md
@@ -42,7 +42,7 @@
 ### 🛠 安装要求
 * PHP 版本 ≥ 5.6(≤ 7.3)
 * mysql 版本 ≥ 5.5
-* mysqli 支持
+* PDO 拓展
 * ZipArchive 支持
 * fileinfo 拓展
 * curl 拓展
diff --git a/application/http/middleware/Initialize.php b/application/http/middleware/Initialize.php
index 94913026..de45a949 100644
--- a/application/http/middleware/Initialize.php
+++ b/application/http/middleware/Initialize.php
@@ -18,14 +18,14 @@ class Initialize
             if ($request->controller(true) !== 'install' || $request->action(true) !== 'index') {
                 return redirect(url('install/index'));
             }
-        }
-
-        // 检测封禁IP
-        $banIp = $this->getConfig('ban_ip');
-        if ($banIp) {
-            $ips = explode(',', str_replace('，', ',', $banIp));
-            if (in_array($request->ip(), $ips)) {
-                throw new HttpResponseException(Response::code(403));
+        } else {
+            // 检测封禁IP
+            $banIp = $this->getConfig('ban_ip');
+            if ($banIp) {
+                $ips = explode(',', str_replace('，', ',', $banIp));
+                if (in_array($request->ip(), $ips)) {
+                    throw new HttpResponseException(Response::code(403));
+                }
             }
         }
 
diff --git a/application/http/middleware/WebAuthenticate.php b/application/http/middleware/WebAuthenticate.php
index 4fa67ae8..f029dfd0 100644
--- a/application/http/middleware/WebAuthenticate.php
+++ b/application/http/middleware/WebAuthenticate.php
@@ -31,7 +31,9 @@ class WebAuthenticate
 
         $user = null;
         if ($uid = Session::get('uid')) {
-            $user = Users::get($uid);
+            if (!$user = Users::get($uid)) {
+                Session::delete('uid');
+            }
         }
 
         if (!in_array($path, $this->paths) && !$user) {
diff --git a/application/index/controller/Install.php b/application/index/controller/Install.php
index a1fd0f0b..7cf956a3 100644
--- a/application/index/controller/Install.php
+++ b/application/index/controller/Install.php
@@ -25,18 +25,18 @@ class Install extends Controller
         $phpVerGt56 = PHP_VERSION >= 5.6;
         $isCurl = function_exists('curl_init');
         $isFileInfo = function_exists('finfo_open');
-        $isMysqli = class_exists('mysqli');
+        $pdo = extension_loaded("pdo_mysql");
         $isZip = class_exists('ZipArchive');
 
         switch ($step) {
             case 1:
                 // 运行环境检测
-                $testing = $phpVerGt56 && $isCurl && $isFileInfo && $isMysqli && $isZip;
+                $testing = $phpVerGt56 && $isCurl && $isFileInfo && $pdo && $isZip;
                 $this->assign([
                     'phpVerGt56' => $phpVerGt56,
                     'isCurl' => $isCurl,
                     'isFileInfo' => $isFileInfo,
-                    'isMysqli' => $isMysqli,
+                    'pdo' => $pdo,
                     'isZip' => $isZip,
                     'testing' => $testing,
                     'dir' => is_writable(app()->getRuntimePath()) && is_writable(app()->getConfigPath()),
diff --git a/application/index/view/install/index.html b/application/index/view/install/index.html
index 776186f6..f10a0943 100644
--- a/application/index/view/install/index.html
+++ b/application/index/view/install/index.html
@@ -76,10 +76,10 @@
       </tr>
       <tr>
         <td align="right">
-          mysqli：
+          PDO 拓展：
         </td>
         <td align="left">
-          {if ($isMysqli) }
+          {if ($pdo) }
           <i class="mdui-icon material-icons mdui-text-color-green">&#xe86c;</i>
           {else/}
           <i class="mdui-icon material-icons mdui-text-color-red">&#xe5c9;</i>