Yealink SIP-T29G User Manual page 199

You can send and receive text messages using the SIP-T29G IP phone. New text
messages can be indicated both acoustically and visually. When receiving a new text
message, the phone will play a warning tone. The power indicator LED will slow flash
red, and the LCD screen will prompt ―n New Text Message(s)‖ (―n‖ indicates the number
of unread text messages. e.g., 1 New Text Message(s)) and an icon
Note
When the phone receives a text message, the text message prompt window will pop up
by default, if you want to disable the feature, contact your system administrator for more
information.
You can store text messages in your phone's Inbox, Sentbox, Outbox or Draftbox. Each
of the boxes can store up to 100 text messages. If the number of the text messages in
one box is more than 100, the phone will directly delete the oldest text message in the
box.
Note
SMS is not available on all servers. Contact your system administrator for more
information.
Advanced Phone Features
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