550 5.2.0 Email Error Message

I recently upgraded to a new laptop running Windows 7 and started using Windows Live Mail as my email program.  I can receive email with no problem.  However, when I try to send email I get an email error message:

 

550 5.2.0 you are not allowed to send mail to E9210

 

When I go to my ISP's website it will let me send email, but not using my email program.  My ISP is no help...they said they can't help me with Norton error messages.

 

I don't know what else to do...HELP!