# Enable Let's Encrypt on Older Windows

Agilicus AnyX requires modern cryptography with a strong chain of trust. This is achieved using [Let's Encrypt](https://letsencrypt.org/).

Some older Microsoft Windows systems are not updated to have the proper cryptographic trust information installed. You should upgrade your Windows installation, but, if this is not possible, you can manually install the certificates.

First, download the .der file from <https://letsencrypt.org/certificates> for each of '[X1](https://letsencrypt.org/certs/isrgrootx1.der) &amp; [X2](https://letsencrypt.org/certs/isrg-root-x2.der)'.

For the X1 der and X2 der, open these on your desktop. You will be prompted to open the certificate manager. From here, Install, and pick the "Trusted Root Certification Authorities".

![Screenshot of Certify The Web application showing the Let's Encrypt certificate generation process on an older Windows system. The interface displays options for domain selection, certificate settings, and task scheduling, guiding users through enabling HTTPS with Let's Encrypt on Windows Server.](https://www.agilicus.com/www/ef749f97-image.png)    ![Let's Encrypt on Older Windows: Enable HTTPS for Secure Connections. Screenshot of Certify The Web ACME client showing successful Let's Encrypt certificate generation on an older Windows system. Secure your website with free SSL/TLS certificates.](https://www.agilicus.com/www/840f874c-image.png)    Now we must import these to the Machine trust as well (above we did your user). To do so, open 'mmc'

![Screenshot of the OpenSSL configuration file showing the required changes to enable Let's Encrypt on older Windows systems. Key lines highlighted include modifications to the openssl.cnf file to ensure compatibility with Let's Encrypt's certificate authority. Specifically, this involves setting the 'CipherString' parameter to 'DEFAULT@SECLEVEL=2' to address potential compatibility issues with older OpenSSL versions and Let's Encrypt certificates on Windows servers. This ensures successful SSL/TLS certificate validation and secure HTTPS connections.](https://www.agilicus.com/www/a11b0196-image-1024x538.png)    Now press 'Control-M'.

![Screenshot of the OpenSSL configuration file on Windows, showing the lines that need to be modified to enable Let's Encrypt for older Windows versions. The image highlights the changes required in the openssl.cnf file, specifically related to enabling TLS SNI for compatibility with Let's Encrypt's certificate validation process. This is a step-by-step guide to configure OpenSSL for Let's Encrypt on older Windows systems. Instructions show how to update the configuration file for successful certificate generation and renewal.](https://www.agilicus.com/www/d1d5597f-image.png)    ![Enabling Let's Encrypt on Older Windows: A step-by-step guide to installing Let's Encrypt certificates on older Windows systems, as shown in the Agilicus FAQ, using a command prompt interface for certificate generation and installation. Secure your website with free SSL/TLS certificates. Agilicus simplifies the process.](https://www.agilicus.com/www/81e59dd0-image-1024x576.png)    ![Enabling Let's Encrypt on Older Windows: A step-by-step guide to installing Let's Encrypt certificates on older Windows systems, overcoming compatibility issues and securing your website with free SSL/TLS certificates. The image shows the process of setting up Let's Encrypt using a compatible ACME client, configuring the necessary settings, and verifying the certificate installation to ensure secure HTTPS connections. Perfect for users needing to secure their legacy Windows servers with Let's Encrypt.](https://www.agilicus.com/www/c2de05c4-image-1024x576.png)    ![Enable Let's Encrypt on Older Windows: A step-by-step guide showing the OpenSSL configuration for generating SSL certificates compatible with older Windows systems, ensuring secure HTTPS connections. This image details the process of updating and configuring OpenSSL for older Windows versions to support Let's Encrypt certificates.](https://www.agilicus.com/www/e69eac7b-image-1024x576.png)    ![Screenshot of Certify The Web ACME client interface on Windows, showing the Let's Encrypt certificate generation process. The interface highlights options for configuring and requesting SSL/TLS certificates for secure HTTPS websites on older Windows systems, as detailed in the Agilicus FAQ.](https://www.agilicus.com/www/65efd9c2-image-1024x576.png)    Select the X1 (and repeat for X2) certificate from earlier.

At this stage you should be able to install the Agilicus Connector.