You don't set it up for additional lines.
Each line has its own MyVerizon account associated with the phone number. You can only view the messages for that line when logged into the MyVerizon account for that number. To view messages for another number, you would have to log out and log back into MyVerizon for the other number.
Good afternoon. Intergrated messaging is very convienent! Thanks to rcschnoor for providing correct information. However, I would like to provide some clarification.
Each line on your account would need to download the Verizon Messaging application on their device first. Once they have installed the application on their device, each line on your account would need to register for it's own My Verizon account online to be able to manage and send messages from the web. For more information regarding Verizon Messaging and intergrating messages online click http://vz.to/13sVCw6 Should you have further questions or concerns, please feel free to reach out to us.
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