Could Not Open Connection To Server

[mandimoo]

Trying to access my sky emails on my Sony experia tablet and all of a sudden, when I try to refresh the emails, I get the above message. I've always been able to access my email till now.

Whilst checking my settings, under security certificate, I came across the message " The application email has requested a certificate. Selecting a certificate will grant the application the ability to use this identity with severs now and in the future." and goes on to tell me that I can download a certificate from an external storage location.

3 questions really.... 1) is this the problem? 2) what do I need to do? (in very layman's terms please, it's took me all night to get this far! 3) what happened to make it stop working?

[mandimoo]

Anyone? Please?