Restarting a TI-84 Plus calculator can be necessary for a variety of reasons, such as when the calculator is frozen, when an error message appears, or when the calculator needs to be reset to its default settings. There are two ways to restart a TI-84 Plus calculator: soft reset and hard reset.
A soft reset restarts the calculator without erasing any data or programs. To perform a soft reset, press the [2nd] key and then the [+] key. The calculator will display the message “Resetting…” and then restart.