This is so frustrating

I love email. I check my email several times a day. Or rather, I TRY to check my email several times a day. I have 4 email accounts. Don't ask why. I have no idea other than being addicted. LOL What frustrates me is that at work there is one account that I can't check. For some reason I get the error page. It's not a blocked site and sometimes I can check it. Some days the site will pull up and let me put in my login and then I get the error message. Some days I can't even do that. I get the error message when I click to the login page. Some days it works just fine. I never have the problem at home. Never. What could be the problem? Could it be the router? Do you think we need to replace the old router with a used cisco one? I'm not sure what the problem is, but I sure do wish they would fix it. *sigh*