Unfortunately a Windows update has caused issues for Chivalry 2 Campaigns as of September 2024.
You can fix this manually by downloading and install certificates from Amazon ( https://www.amazontrust.com/repository/ ).
You would need to download the 5 DER files under the Root CAs section.
Double click on the files, and follow instructions to install.
We will be working on a full fix if you do not want to follow these steps at this time.
