I use a PC at home and a Surface tablet when on the road. It sometimes is months before I access my webmail account on the Surface. On this road trip I tried to access my webmail on the Surface and found that it has 644 emails and they will not open. I suspect it is a capacity issue.
I am prepared to delete all messages dated before October 24 so that I can see only the current ones.
Can anyone suggest what I should do to gain access again.
Shouldn't be a capacity issue, as webmail leaves all the info on the server, and stores nothing on the computer.
Have you restarted the Surface, and made a fresh login to webmail?
It sounds as if you have set up your email client on your home PC not to delete incoming messages on the server, so they're all there when you sign in to webmail. The whole question of mail management is tricky and subject to personal preference--IMAP or POP3, remove from server or not. Unfortunately, they're not completely simple issues.
I don't know about Telus webmail specifically, but I have seen webmails with thousands of messages, so I doubt that it's a capacity problem.