diff --git a/en_US/upgrade/0-upgrade.iredmail.1.3.1-1.3.2.md b/en_US/upgrade/0-upgrade.iredmail.1.3.1-1.3.2.md
index 376a5186..910c4910 100644
--- a/en_US/upgrade/0-upgrade.iredmail.1.3.1-1.3.2.md
+++ b/en_US/upgrade/0-upgrade.iredmail.1.3.1-1.3.2.md
@@ -26,21 +26,11 @@ so that you can know which version of iRedMail you're running. For example:
 
 ### SOGo: yum and apt repositories for SOGo v4 has been removed permanently by upstream
 
-SOGo team removed nightly builds for SOGo v4 + v3 permanently (FYI: <https://sogo.nu/bugs/view.php?id=5157>), __ALL__ servers must update yum/apt repository files and switch to SOGo v5. Upgrading is simple, no SQL structure changes from v4 to v5.
+SOGo team removed nightly builds for SOGo v4 + v3 permanently (FYI: <https://sogo.nu/bugs/view.php?id=5157>), __ALL__ servers must update yum/apt repository files and switch to SOGo v5.
 
-- On CentOS, please update file `/etc/yum.repos.d/sogo.repo`, replace version number `4` by `5`, then run:
+Please follow our tutorial to upgrade:
 
-```
-yum clean metadata
-yum update
-```
-
-- On Debian/Ubuntu, please update file `/etc/apt/sources.list.d/sogo.list` (or `sogo-nightly.list`), replace version number `4` by `5`, then run:
-
-```
-apt-get update
-apt-get upgrade
-```
+- [Upgrade SOGo from v4 to v5](./upgrade.sogo.4.to.5.html)
 
 ### Upgrade iRedAPD (Postfix policy server) to the latest stable release (4.6)
 
diff --git a/html/upgrade.iredmail.1.3.1-1.3.2.html b/html/upgrade.iredmail.1.3.1-1.3.2.html
index 92363cb8..a02f14cb 100644
--- a/html/upgrade.iredmail.1.3.1-1.3.2.html
+++ b/html/upgrade.iredmail.1.3.1-1.3.2.html
@@ -63,21 +63,11 @@ so that you can know which version of iRedMail you're running. For example:</p>
 </code></pre>
 
 <h3 id="sogo-yum-and-apt-repositories-for-sogo-v4-has-been-removed-permanently-by-upstream">SOGo: yum and apt repositories for SOGo v4 has been removed permanently by upstream</h3>
-<p>SOGo team removed nightly builds for SOGo v4 + v3 permanently (FYI: <a href="https://sogo.nu/bugs/view.php?id=5157">https://sogo.nu/bugs/view.php?id=5157</a>), <strong>ALL</strong> servers must update yum/apt repository files and switch to SOGo v5. Upgrading is simple, no SQL structure changes from v4 to v5.</p>
+<p>SOGo team removed nightly builds for SOGo v4 + v3 permanently (FYI: <a href="https://sogo.nu/bugs/view.php?id=5157">https://sogo.nu/bugs/view.php?id=5157</a>), <strong>ALL</strong> servers must update yum/apt repository files and switch to SOGo v5.</p>
+<p>Please follow our tutorial to upgrade:</p>
 <ul>
-<li>On CentOS, please update file <code>/etc/yum.repos.d/sogo.repo</code>, replace version number <code>4</code> by <code>5</code>, then run:</li>
+<li><a href="./upgrade.sogo.4.to.5.html">Upgrade SOGo from v4 to v5</a></li>
 </ul>
-<pre><code>yum clean metadata
-yum update
-</code></pre>
-
-<ul>
-<li>On Debian/Ubuntu, please update file <code>/etc/apt/sources.list.d/sogo.list</code> (or <code>sogo-nightly.list</code>), replace version number <code>4</code> by <code>5</code>, then run:</li>
-</ul>
-<pre><code>apt-get update
-apt-get upgrade
-</code></pre>
-
 <h3 id="upgrade-iredapd-postfix-policy-server-to-the-latest-stable-release-46">Upgrade iRedAPD (Postfix policy server) to the latest stable release (4.6)</h3>
 <div class="admonition attention">
 <p class="admonition-title">Attention</p>