openssl base64 -in certificate.crt -out cert.b64
The fastest method for Windows 11 is using the built-in winget tool. Open or PowerShell as an administrator. Run the command: winget install openssl . Follow the on-screen prompts to complete the installation. 2. The Traditional Way: Third-Party Installers openssl for windows 11
Access Windows files: openssl req -new -key /mnt/c/Users/YourName/key.pem ... openssl base64 -in certificate
Create a san.cnf file:
[ req_distinguished_name ] countryName = Country Name (2 letter code) countryName_default = US stateOrProvinceName = State or Province Name stateOrProvinceName_default = California localityName = Locality Name 0.organizationName = Organization Name organizationalUnitName = Organizational Unit Name commonName = Common Name (FQDN) commonName_default = localhost emailAddress = Email Address Follow the on-screen prompts to complete the installation
OpenSSL relies on a configuration file to define default certificate fields, CA policies, and extensions. On Windows 11, the official installer places openssl.cnf in C:\Program Files\OpenSSL-Win64\bin\cnf . However, OpenSSL often fails to locate it, producing errors like: