Opening webmail

When I open webmail from a mobile device, I go directly to my Cox inbox.  When I open webmail from my PC or laptop, I'm required to go through several steps to access my Cox inbox; I must enter my login, password, wait and then enter my zip code.  It makes no sense to me that I am able to access my Cox email directly from a mobile device, but not from my PC.

Is there a solution to having to go through all these steps on my PC?

I'm also baffled as to why some of my Cox email in my inbox just disappears.  It's very frustrating.