The usual way to change instruments is to right click the staff, select Staff Properties, press the Change Instrument button, and select tenor saxophone from the list. If that doesn't solve the problem for you, please use the Support forum (Help / Ask for Help, not Help / Report a Bug) to ask for further assistance. When you do so, please attach the score you are having trouble with and describe in more detail what went wrong when you tried changing instrument.
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The usual way to change instruments is to right click the staff, select Staff Properties, press the Change Instrument button, and select tenor saxophone from the list. If that doesn't solve the problem for you, please use the Support forum (Help / Ask for Help, not Help / Report a Bug) to ask for further assistance. When you do so, please attach the score you are having trouble with and describe in more detail what went wrong when you tried changing instrument.