How are you trying to send/receive mail? Are you logging into your mail accounts via your BB Browser? You shouldn't need to. You can add your accounts to your device and they will have an icon for each mail account.
Here is how to add an email account to your device: How to add / delete email addresses - BlackBerryFAQ
Here is how to resend your service books: How do I resend my service books? - BlackBerryFAQ