http://exact.help/plesk-manual-ssl

After purchasing an SSL for use with Plesk hosting, there will be a few steps needed to configure and issue the certificate. Follow the guide here to clarify how to complete these steps and issue your certificate.

Before beginning, make sure you have:

-An SSL purchased in the ExactHosting account.

-Access to the Plesk account.

-Create one of the following emails for SSL approval and certificate sending (Note: Replace example.com with your domain name):

admin@example.com
administrator@example.com
postmaster@example.com
hostmaster@example.com
webmaster@example.com

*You may alternatively create a forward only address to an external email, or an alias address to another domain email if no mailboxes are available.

*If your email services are not with ExactHosting, you will need to work with the mail provider to accomplish mailbox/forward/alias creation prior to configuring the certificate.

Once you've ensured the certificate is purchased, the approval email is created and you have access to the hosting account, you can move on to configuring the SSL.

STEP 1: GENERATE THE CSR ON PLESK

A. Login to the Plesk control panel.

B. Locate the domain name and select the option for SSL

C. Name the certificate, fill out all required contact details and select Request.

D. The SSL just created should now appear listed in the account as pictured below. Select the SSL name to view/copy the CSR.

STEP 2: CONFIGURE THE CERTIFICATE

A. Login to the ExactHosting account.

B. Navigate to Services, then My Services. Select the Active button associated to the SSL.

C. Select the blue link for Configure Now.

Select Plesk as the Web Server Type
Input the CSR copied in step 1-D
Enter the Administrative Contact Information. These should be the same details entered in Step 1-C.
Select to continue to move to the next step

D. Choose the corresponding email from the Certificate Approver Email list, which was created prior to beginning, and select Continue.

STEP 3: APPROVE AND INSTALL

A. Check the email assigned as approver for a message from the certificate issuer, either Comodo or Geotrust. An example of what the approval email subject line and sending address may look like is below.

B. Locate the approval link, and copy and paste the link to a new window to click the approval button.

C. After approval, an email including a copy of the SSL Certificate will be sent. An Example of what the email subject line and sending address might look like is below.