I have been having this problem for months now and it seems to fall on deaf ears with Cox. I see a lot of other people are having the same issues. I have done those steps others say to do and the email would open intermittently on sparse occassions but the same problem still persists. I have not been able to my email on my Windows operating system Laptop utilizing Chrome, Edge, Firefox and Opera for weeks now.  The only place I have been able to open my webmail is on my iPhone which appears to be un-effected.  Cox is aware the new web-mail is flawed and yet they still have done nothing about it and have not reverted back to the old system until they can fix it's glitches. So tired of seeing versions of this message over and over again:  

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