Webmail and POP3 mailboxes don't play well together unfortunately. The slowness that you're experiencing is due to the number of emails you have. The webmail client we use will read every single one of those emails before presenting you with the Inbox view as it needs to parse those mails to pull things out such as the From:, Subject: and Date: headers. I can't be sure without checking but I also believe that it also checks the email body for attachments etc. Every time you return to the Inbox view it repeats this process.
As Phil's already stated, our mail system was originally offered as a 'transit' service, as POP3 was originally designed, ie it's just somewhere to hold the email until such time as you can properly download it. As such, the webmail offered was a basic service to allow access to email whilst away from home/the office.
I did start a personal (ie in my own time) project to write a better webmail service that played nicely with POP3 by using a database to remember what the mailbox contained and only update the changes. As often happens with personal projects other things (family, friends, trying to get fitter etc) have taken priority, resulting in development stalling. At this time I am uncertain as to whether I will continue to write the application.
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Jerry Nicholls
Principal Systems Engineer
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