If you need an new SSL Certificate for your Domain, and you want to use Let’s Encrypt, you may not want to wait until it will be natively integrated into Mail-in-a-Box. So - why not getting it trough shell? - Because you have not enough knowledge or understanding of the Shell? No Problem. You can use this great web based tool to get an free certificate in 5 minutes:
Created by diafygi. Thank you for that
(The Source Code of this static page is open, and maybe we can use it for the MiaB LE Integration too @JoshData)