The customer domain brings also issues related to SSL certificates. In these days is very recommended to use encryption and SSL certificates for webshops - if you do not have a SSL certificate, no online payments will work in your shop, and furthermore, Google penalizes webshops without SSL certificates. But certificates to the customer domain have to be solved and provided by the customer for a specific domain. We can’t help with it, because we don‘t have access to the customer domain to validate it. To activate the customer’s SSL certificate we need to receive from the customer Public part of the SSL certificate and SSL certificate PRIVATE key (all in text form in one or two files).
Which format the customer receives from a certification authority can be different. In case it will be in text form, it is enough. If it will be in the PFX file format, we need a password used for the creation of this PFX file and then we can extract necessary data from it.
There is some detailed information: