Welcome to the Dell community.
Depending on the system model, you can perform the following key combinations to enable / disable the touchpad
1. Fn+F3 or simply F3
2. Some system have a separate key on the right of F12 key with a picture of a touchpad and X on it which enables and disables the touchpad
3. Remove the battery and the adaptor from the system and any external devices, then press and hold the power/ start button for 30 seconds and release. Then start the system. This works many times
Please revert back with your observation.
Glad to assist you.
Social Outreach Professional
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