http://bis.na.blackberry.com/html/

Is forwarding or re-directing to T-Mobile.com

Anyone have any clue why or how to access the BIS site?

You need to include your carrier's name in the link; for example:
For T-Mobile users it looks like the BIS must be accessed through the My T-Mobile website: T-Mobile - Blackberry Internet E-mail

Its telling me my username is not known?

use this address: https://bis.na.blackberry.com/html?brand=vzw

Thank you!

That is for Verizon only (vzw).

Correct, in his previous posts he said he has VZW..

I thought he had T-Mo