diff --git a/docs/ikev2-howto-zh.md b/docs/ikev2-howto-zh.md
index 20187ac..3dd65af 100644
--- a/docs/ikev2-howto-zh.md
+++ b/docs/ikev2-howto-zh.md
@@ -433,7 +433,7 @@ wget https://git.io/ikev2setup -O ikev2.sh && sudo bash ikev2.sh
 
 ## 已知问题
 
-1. Windows 自带的 VPN 客户端可能不支持 IKEv2 fragmentation。在有些网络上，这可能会导致连接错误或其它连接问题。你可以尝试换用 <a href="clients-zh.md" target="_blank">IPsec/L2TP</a> 或 <a href="clients-xauth-zh.md" target="_blank">IPsec/XAuth</a> 模式。
+1. Windows 自带的 VPN 客户端可能不支持 IKEv2 fragmentation（该功能<a href="https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-ikee/74df968a-7125-431d-9c98-4ea929e548dc" target="_blank">需要</a> Windows 10 v1803 或更新版本）。在有些网络上，这可能会导致连接错误或其它连接问题。你可以尝试换用 <a href="clients-zh.md" target="_blank">IPsec/L2TP</a> 或 <a href="clients-xauth-zh.md" target="_blank">IPsec/XAuth</a> 模式。
 1. Ubuntu 18.04 用户在尝试将生成的 `.p12` 文件导入到 Windows 时可能会遇到错误 "输入的密码不正确"。这是由 `NSS` 中的一个问题导致的。更多信息请看 <a href="https://github.com/hwdsl2/setup-ipsec-vpn/issues/414#issuecomment-460495258" target="_blank">这里</a>。
 1. 如果你使用 strongSwan Android VPN 客户端，则必须将服务器上的 Libreswan <a href="../README-zh.md#升级libreswan" target="_blank">升级</a>到版本 3.26 或以上。
 
diff --git a/docs/ikev2-howto.md b/docs/ikev2-howto.md
index 0de367b..af2efc0 100644
--- a/docs/ikev2-howto.md
+++ b/docs/ikev2-howto.md
@@ -433,7 +433,7 @@ In certain circumstances, you may need to revoke a previously generated VPN clie
 
 ## Known issues
 
-1. The built-in VPN client in Windows may not support IKEv2 fragmentation. On some networks, this can cause the connection to fail or have other issues. You may instead try the <a href="clients.md" target="_blank">IPsec/L2TP</a> or <a href="clients-xauth.md" target="_blank">IPsec/XAuth</a> mode.
+1. The built-in VPN client in Windows may not support IKEv2 fragmentation (this feature <a href="https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-ikee/74df968a-7125-431d-9c98-4ea929e548dc" target="_blank">requires</a> Windows 10 v1803 or newer). On some networks, this can cause the connection to fail or have other issues. You may instead try the <a href="clients.md" target="_blank">IPsec/L2TP</a> or <a href="clients-xauth.md" target="_blank">IPsec/XAuth</a> mode.
 1. Ubuntu 18.04 users may encounter the error "The password you entered is incorrect" when trying to import the generated `.p12` file into Windows. This is due to a bug in `NSS`. Read more <a href="https://github.com/hwdsl2/setup-ipsec-vpn/issues/414#issuecomment-460495258" target="_blank">here</a>.
 1. If using the strongSwan Android VPN client, you must <a href="../README.md#upgrade-libreswan" target="_blank">upgrade Libreswan</a> on your server to version 3.26 or above.