Note that to add text messaging to your account, you or your manager will have to have set that up already. {Click here} for an in-depth article on how to do this.
Add to User Account
Go to My Preferences.
Click Texting.
Select the desired provider.
Select the Text message sender & click Update.
A text message sender is a number you want to send the message from; this is set up on your text message provider side.
