The TradeXchange Mailbox ID and password is used for sending/receiving of permit to Tradenet. Without it, you will not be able to do send/receive.
Take note that the password may be different from your TradeWeb login in future if you reset or change it.
If you need to contact CrimsonLogic about ID and password issues, please tell us whether you are referring to the TradeWeb one, or the TradeXchange Mailbox one. This distinction applies to password re-set and re-activate as