diff --git a/install.sh b/install.sh
index b240976..580a9a7 100644
--- a/install.sh
+++ b/install.sh
@@ -1358,15 +1358,25 @@ deploy_certbot() {
         print_success "Certbot SSL证书申请成功"
         return 0
     else
-        print_error "Certbot SSL证书申请失败"
-        echo ""
-        print_warning "常见失败原因:"
-        echo "  1. 域名未正确解析到此服务器"
-        echo "  2. 防火墙阻止了80端口"
-        echo "  3. Nginx未正确配置或未启动"
-        echo "  4. Let's Encrypt速率限制"
-        echo ""
-        return 1
+        # 检查证书是否已存在
+        if [[ -d "/etc/letsencrypt/live/${DOMAIN}" ]]; then
+            print_warning "检测到证书已存在，使用已有证书"
+            mkdir -p /etc/nginx/ssl
+            ln -sf "/etc/letsencrypt/live/${DOMAIN}/fullchain.pem" "/etc/nginx/ssl/${DOMAIN}.crt"
+            ln -sf "/etc/letsencrypt/live/${DOMAIN}/privkey.pem" "/etc/nginx/ssl/${DOMAIN}.key"
+            print_success "已有证书已链接到Nginx目录"
+            return 0
+        else
+            print_error "Certbot SSL证书申请失败"
+            echo ""
+            print_warning "常见失败原因:"
+            echo "  1. 域名未正确解析到此服务器"
+            echo "  2. 防火墙阻止了80端口"
+            echo "  3. Nginx未正确配置或未启动"
+            echo "  4. Let's Encrypt速率限制"
+            echo ""
+            return 1
+        fi
     fi
 }
 
@@ -1486,18 +1496,25 @@ deploy_acme_letsencrypt() {
     fi
 
     # 使用webroot模式申请证书（更可靠）
+    # 先尝试正常申请，如果证书已存在则使用--force强制更新
     if ~/.acme.sh/acme.sh --issue -d "$DOMAIN" --webroot "${PROJECT_DIR}/frontend"; then
         print_success "证书申请成功"
     else
-        print_error "证书申请失败"
-        echo ""
-        print_warning "常见失败原因:"
-        echo "  1. 域名未正确解析到此服务器"
-        echo "  2. Nginx未正确配置或未启动"
-        echo "  3. 80端口被占用或防火墙阻止"
-        echo "  4. 前端目录权限不足"
-        echo ""
-        return 1
+        # 检查是否是因为证书已存在
+        if ~/.acme.sh/acme.sh --list | grep -q "$DOMAIN"; then
+            print_warning "检测到证书已存在，使用已有证书"
+            print_success "将直接安装现有证书"
+        else
+            print_error "证书申请失败"
+            echo ""
+            print_warning "常见失败原因:"
+            echo "  1. 域名未正确解析到此服务器"
+            echo "  2. Nginx未正确配置或未启动"
+            echo "  3. 80端口被占用或防火墙阻止"
+            echo "  4. 前端目录权限不足"
+            echo ""
+            return 1
+        fi
     fi
 
     # 安装证书
@@ -1646,8 +1663,14 @@ deploy_acme_zerossl() {
     if ~/.acme.sh/acme.sh --server zerossl --issue -d "$DOMAIN" --webroot "${PROJECT_DIR}/frontend"; then
         print_success "证书申请成功"
     else
-        print_error "证书申请失败"
-        return 1
+        # 检查是否是因为证书已存在
+        if ~/.acme.sh/acme.sh --list | grep -q "$DOMAIN"; then
+            print_warning "检测到证书已存在，使用已有证书"
+            print_success "将直接安装现有证书"
+        else
+            print_error "证书申请失败"
+            return 1
+        fi
     fi
 
     # 安装证书
@@ -1796,8 +1819,14 @@ deploy_acme_buypass() {
     if ~/.acme.sh/acme.sh --server buypass --issue -d "$DOMAIN" --webroot "${PROJECT_DIR}/frontend"; then
         print_success "证书申请成功"
     else
-        print_error "证书申请失败"
-        return 1
+        # 检查是否是因为证书已存在
+        if ~/.acme.sh/acme.sh --list | grep -q "$DOMAIN"; then
+            print_warning "检测到证书已存在，使用已有证书"
+            print_success "将直接安装现有证书"
+        else
+            print_error "证书申请失败"
+            return 1
+        fi
     fi
 
     # 安装证书