diff --git a/_layouts/default-layout.html b/_layouts/default-layout.html
index 44e8c1a5..bf710793 100644
--- a/_layouts/default-layout.html
+++ b/_layouts/default-layout.html
@@ -15,27 +15,27 @@
 </style>
 
 <body>
-    <div class="headWrapper">
+    <header class="headWrapper">
         {%- include page_header.html -%}
-    </div>
+    </header>
     {%- include dwtNav.html -%}
     <div class="sideBarIcon"><i class="fa fa-list" style="margin-right: 5px;"></i> Table of contents</div>
-    <div class="container" id="categoryMenuTree">
+    <main class="container" id="categoryMenuTree">
         <div class="row">
-            <div class="sideBar col-xs-12 col-md-3 hide-xs hide-sm">
+            <aside class="sideBar col-xs-12 col-md-3 hide-xs hide-sm">
                 <div id="sideBarCnt">
                     <div class="docSearchPart" style="margin-top: 30px;">
                         <input id="txtSearch" class="search" type="text">
                     </div>
-                    <div class="mainPage">
+                    <nav class="mainPage">
                         <ul id="fullTreeMenuListContainer" name="listLevel1">
                             {%- assign treeList = site.data.full_tree.tree_list -%}
                             {%- include liquid_generateFullTree.html treeList=treeList -%}
                         </ul>
-                    </div>
+                    </nav>
                 </div>
-            </div>
-            <div class="docContainer col-xs-12 col-md-9">
+            </aside>
+            <section class="docContainer col-xs-12 col-md-9">
                 <div id="docHead" class = "head row hide-xs hide-sm">
                     {%- include main-page-head.html -%}
                 </div>
@@ -62,9 +62,9 @@
                         <div class="lds-ring"><div></div><div></div><div></div><div></div></div>
                     </div>
                 </div>
-            </div>
+            </section>
         </div>
-    </div>
+    </main>
 
     <div class="history list" id="categoryMenuTree_history">
         <div class="container">
@@ -75,9 +75,9 @@
         </div>
     </div>
 
-    <div id="footerWrapper">
+    <footer id="footerWrapper">
         {%- include page_footer.html -%}
-    </div>
+    </footer>
 
     <script type="text/javascript">
         $(".currentVersion").text("latest version (18.1)");
diff --git a/faq/failed-to-load-resource.md b/faq/failed-to-load-resource.md
index 40cb4005..19221214 100644
--- a/faq/failed-to-load-resource.md
+++ b/faq/failed-to-load-resource.md
@@ -21,47 +21,46 @@ You get an error message that says **"Failed to load resource: net::ERR_CERT_DAT
 
 By default, “127.0.0.1” is used for service connection. "127.0.0.1" uses a self-signed certificate because it is an internal IP address, if your environment requires high level security, self-signed certificates may not be accepted. Moreover, Android OS or Chrome OS does not accept connection between browsers and Dynamsoft Service via "127.0.0.1".
 
-1. In case, you used our expired certificate - local.dynamsoft.com, as an official domain which uses a VeriSign’ed certificate. The old "local.dynamsoft.com" certificate expired on <font color=red>January 9th, 2023</font> and the new certificate will expire on <font color=red>December 8th, 2023</font>
-   > ___Please note:___ _all official certificates issued by 3rd party come with an expiry date - generally one year. This means that each year the certificate will need to be updated if local.dynamsoft.com is used._
+In case, you used our expired certificate - local.dynamsoft.com, as an official domain which uses a VeriSign’ed certificate. The old "local.dynamsoft.com" certificate expired on <font color=red>January 9th, 2023</font> and the new certificate will expire on <font color=red>December 8th, 2023</font>
+> ___Please note:___ _all official certificates issued by 3rd party come with an expiry date - generally one year. This means that each year the certificate will need to be updated if local.dynamsoft.com is used._
 
-2. Your own domain certificate expired.
+<!-- 2. Your own domain certificate expired. -->
 
 <!-- In this case, if you are trying to access an application that integrates a version of Dynamic Web TWAIN V15.3 ~ V17.2.5, you will get the error. Because the old "local.dynamsoft.com" certificate expired on <font color=red>January 9th, 2023</font>.  -->
 
 ### Resolution
 
 - **No High Level Security Requirement**:
-
   Set back to self-signed certificate "127.0.0.1" by comment the line `Dynamsoft.WebTwainEnv.Host = "local.dynamsoft.com"` or `Dynamsoft.DWT.Host="local.dynamsoft.com"` out. No need to worry about the expiry date of the certificate anymore.
 
-- **High Level Security Requirement**
-
-1. Set back to "127.0.0.1" by comment the line `Dynamsoft.WebTwainEnv.Host = "local.dynamsoft.com"` or `Dynamsoft.DWT.Host="local.dynamsoft.com"` out.
-2. Replace the certificate of "127.0.0.1" with your own domain certificate and build Service MSI yourself. More information refer to [How can I change the certificate of the Dynamsoft Service?](https://www.dynamsoft.com/web-twain/docs/faq/change-dynamsoft-service-certificate.html)
-
-<!-- - **[Not Recommend] If you have to use "local.dynamsoft.com", the following methods can be taken:**
-    - Method 1. Upgrade to V18.0+ which comes with a valid certificate 
-    - Method 2. If you must fix the issue on a few client machines immediately, manually update the following cert files on the client-side machine. Click <a href="https://tst.dynamsoft.com/public/download/dwt/newcert/local.dynamsoft.com/newcert.zip" target="_blank">here</a> to download the new certificate and use the new server.pem.ldsc & server_key.pem.ldsc to replace the old one under **`C:\Windows\SysWOW64\Dynamsoft\DynamsoftService(DynamsoftServicex64)\cert`**.
-      > Note: the new certificate from Dynamsoft will expire on <font color=red>December 8th, 2023</font>. This means you must update the certificate again after this certificate expires.
-    - Method 3. <a href="{{site.about}}getsupport.html" target="_blank">Contact Dynamsoft</a> for a new MSI for client-side. -->
-     
-<!-- - For v17.2 or higher versions, you can use the new API <a href="{{site.info}}api/Dynamsoft_WebTwainEnv.html#updatecert" target="_blank">UpdateCert</a> to automatically update client side certificate before it expires. **Please go to dynamsoft.webtwain.install.js file in the Resource Folder and search the keyword "OnSSLCertInfo"**, add the following lines of code:
-    ```javascript
-    Dynamsoft.OnSSLCertInfo = function (sslExpiredDate) {
-        if ((sslExpiredDate - new Date()) / 86400000 < 15) { // Automatically updates 15 days before expiration
-            Dynamsoft.DWT.UpdateCert(
-                "Url to download the new certificate.", //E.g. http://xxx.com/cert.zip. server.pem.ldsc & server_key.pem.ldsc should be in cert.zip.
-                function () {
-                    //Success callback
-                },
-                function (errorCode, errorString) {
-                    console.log(errorString);
+- **High Level Security Requirement (<font color=red>Please pay attention: you need to replace the certificate annually due to expiration</font>)**
+  1. (<u>**Recommend**</u>) Set back to self-signed certificate "127.0.0.1". Dynamsoft understand the importance of information security and are committed to remaining one of the most security-compliant companies in the industry. Starting from April 9,2021, Dynamsoft become ISO 27001 certified. Though you are using a self-sign certificate, but all connections are limited to the device itself (127.0.0.1) which ensures the security in most cases.
+
+  2. If you have to use "local.dynamsoft.com", the following methods can be taken:
+        - Method 1 (<u>**Recommend**</u>). Take the advantage of new feature -- **Remote Scan** which released in v18.0. With Remote Scan, you can limit the number of Dynamsoft Service Installations to the minimum. For more details, please refer to [What is Remote Scan](https://www.dynamsoft.com/remote-scan/docs/introduction/).
+        
+        - Method 2. If you must fix the issue on a few client machines immediately, manually update the following cert files on the client-side machine. Click <a href="https://tst.dynamsoft.com/public/download/dwt/newcert/local.dynamsoft.com/newcert.zip" target="_blank">here</a> to download the new certificate and use the new server.pem.ldsc & server_key.pem.ldsc to replace the old one under **`C:\Windows\SysWOW64\Dynamsoft\DynamsoftService(DynamsoftServicex64)\cert`**. Then restart Dynamsoft Service.
+            > Note: the new certificate from Dynamsoft will expire on <font color=red>December 8th, 2023</font>. This means you must update the certificate again after this certificate expires.
+
+        - Method 3. <a href="{{site.about}}getsupport.html" target="_blank">Contact Dynamsoft</a> for a new MSI for client-side.
+
+        - Method 4 (<u>**Convenience but not recommend**</u>). For v17.2 or higher versions, you can use the new API <a href="{{site.info}}api/Dynamsoft_WebTwainEnv.html#updatecert" target="_blank">UpdateCert</a> to automatically update client side certificate before it expires. **Please go to dynamsoft.webtwain.install.js file in the Resource Folder and search the keyword "OnSSLCertInfo"**, add the following lines of code:
+            ```javascript
+            Dynamsoft.OnSSLCertInfo = function (sslExpiredDate) {
+                if ((sslExpiredDate - new Date()) / 86400000 < 15) { // Automatically updates 15 days before expiration
+                    Dynamsoft.DWT.UpdateCert(
+                        "-https://tst.dynamsoft.com/public/download/dwt/newcert/local.dynamsoft.com/newcert.zip", //E.g. http://xxx.com/cert.zip. server.pem.ldsc & server_key.pem.ldsc should be in cert.zip.
+                        function () {
+                            //Success callback
+                        },
+                        function (errorCode, errorString) {
+                            console.log(errorString);
+                        }
+                    );
                 }
-            );
-        }
-    };
-    ``` -->
-
+            };
+            ```
+            ***Please be aware of that the download may not work properly in all environments due to your company's security policy.***
 <!--
 
  1) Go to service directory, and find _DSConfiguration.ini_.  
