In the Web Admin where your CSR was created, simply copy and paste the contents of the certificate files to the 'SSL Certificate(s)' field. The Primary Certificate (your_domain_name.crt) must be first, and the Intermediate Certificate (E-Tugra_Root.crt) second with no line of space between the two.
(Your Primary certificate: your_domain_name.crt)
(Your Intermediate certificate: E-Tugra_Root.crt)
To copy the SSL Certificates, the certificates can be best opened in text format with a text editor that retains the block format of the file such as WordPad.
Press Save and restart SurgeMail to begin using the new Certificate.