Win11 - DNS lookup is slow when connected to AWS VPN

Question

I need to connect to works VPN using AWS VPN Client v3.5.0, but when I do this I get severe lag on DNS lookups for public domains

![Slow dns lookup](/media/postImages/original/IMxefJm-tqSm2KAozCHT-nyA)

This does not happen when the VPN is disconnected and it is not an issue for any other team members, however as far as I know they are not on Win11.

I have:

* Checked that there is no other VPN client installed
* Disabled IPV6 on both my wi-fi connection and the vpn connection
* Installed and ran wireshark which apparently fixed a similar issue with win10 for some people
* Ran `Set-NetIPInterface -InterfaceAlias Wi-Fi -InterfaceMetric 4` [advised by someone with a similar issue](https://gitlab.com/openconnect/openconnect/-/issues/20)
* Reinstalled the VPN client
* Updated windows to latest

Windows details:
```
Edition	Windows 11 Pro
Version	22H2
Installed on	‎17/‎05/‎2023
OS build	22621.1778
Experience	Windows Feature Experience Pack 1000.22642.1000.0
```

Answer

I found the following article.  
After installing the preview release KB5025305 or later updates for Windows 11 22H2, the communication speed when connecting to a VPN may become abnormally slow in some environments.  
https://www.bleepingcomputer.com/news/microsoft/microsoft-investigates-slow-windows-vpn-speeds-after-may-updates/

This seems consistent with your version.  
https://support.microsoft.com/en-us/topic/may-9-2023-kb5026372-os-build-22621-1702-ce93c18e-e819-458f-abcf-dc7154ce7e40

The article states that uninstalling the update will solve the problem.  
So it may be a good idea to uninstall it temporarily.

Win11 - DNS lookup is slow when connected to AWS VPN

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