Do I need a secure mail key if I am just using webmail?

All of a sudden this week, I have been unable to access my webmail using my laptop. I've tried 3 different browsers. I've deleted cookies and cache. I also had the same problem on the mail app of my phone but I created a secure mail key and that fixed the problem. However, on my laptop, I just use a web browser to read my email, not Outlook or any app. But I continue to get a cannot connect error. Nothing has changed on our network. Any suggestions?