Can't get piping to work

[meeven]

I have spent close to 3 hours now getting this to work and all I have is a good dose of frustration. I am not sure what I need to get this correct and there are areas that I wish were more clear:

 

• I have installed WHMCS on a subdomain - http://portal.example.com - In cPanel, subdomains actually get created as a subdirectory within public_html, so this is actually public_html/portal/
   
  Now, if my support department email addresses are support@example.com and sales@example.com, which ticket import method should I use? The cron method or the email forwarders method? I ask because it says in the wiki that for support department email addresses belonging to a different domain from where WHMCS is installed, one has to use the cron method.
  
• The wiki says to use just public_html/whmcs/pipe/pipe.php if using the x3 theme. I am using the latest stable version of cPanel, but even there it automatically gets converted to |/home/example/public_html/portal/pipe/pipe.php
  
• I then tried sparky's advice to change permissions for pop.php and pipe.php to 744 as I am running suPHP, but it didn't help.
  
• I even tried the cron.php method (POP3 import), but that had the effect or removing all the existing emails from the mailbox and importing them into WHMCS. New emails sent were not imported at all.
  

[meeven]

I submitted a ticket and was initially advised to use the piping method. Then I realised the email is hosted externally and the answer then was that only the POP import method would work.