The AutoACME project wants to bring Let's Encrypt (and possibly other ACME-based certificate services) to Windows and IIS. There is of course the letsencrypt-win-simple project, but I was not able to use it reliably for the purposes I had in mind. So I decided to write my own management solution based on the Certes library and some other technologies being part of IIS.

Download the latest release from GitHub.

• Fully automated operation after initial setup
• Supports unlimited number of servers and sites
• Does not require any modification of web sites
• Does not require administration rights
• Does not interact with IIS setup during operation
• Allows use of certificates outside of IIS and web
• Supports web farms
• Supports SAN (multiple host names) certificates
• Supports wildcard certificates (requires DNS challenge)

AutoACME consists of two command-line utilities, generally intended to be run in non-interactive mode from batch files or scheduled tasks

• autoacme.exe handles the ACME communication and is completely independent on IIS (you can use it even without IIS installed).
• aasync.exe can optionally synchronize IIS settings with AutoACME, either by automatically requesting certs for all HTTPS sites or even by enabling HTTPS on HTTP-only sites.

• Getting started with AutoAcme
• Synchronization with IIS
• Command line reference
• Configuration file reference
• AutoACME in a web farm environment (advanced)