Cannot send e-mail from one computer

I cannot send e-mail from one account on a single computer.  When we travel, my wife and I  both use the same ASUS Transformer Prime, which is a  pad computer, for our e-mails, which are both Verizon accounts.  When she logs on, she can send and receive just fine.  But when I log on I can receive, but when I try to send the "send" button grays out but nothing else happens.  I don't have this problem when I log on with any other computer.  Any thoughts?