Editing Installing Let's Encrypt SSL Certificates On Namecheap Hosting (section)

=== Certificate failing to verify using .well-known challenge ===

'''Use case'''

* Log into the server using ssh.
* Run `acme.sh` script from the command line to renew certificate. 
* There will be errors to effect of `"verify error"` and `"invalid response from [domain]/.well-knonwn/acme-challenge/..."`.

'''Cause'''

Permissions errors prevent the script from writing the file to `.well-known/acme-challenge/` that is used to verify ownership of the domain.

'''Fix'''

The last time this happened, I compared the permissions for the web roots and `.well-known` directories for two sites hosted on the same server where one site's certificate was being renewed and the other was failing. I could not find any differences in the permissions.

What I ended up doing was to move the root directory of the site, create a new directory for the site, put a potboiler index html page in the directory, and then run the acme script. After this allowed me to renew the certificate, I copied all the content from the original directory back into the new one.

'''Also!''' Remember that the root of many of the web apps is in the `app/` subdirectory! When issuing the certificate make sure to set the web root option appropriately, e.g. `--webroot ~/mydomain.com/app`