Hello Marc. I'm Greg, here to help you with this.
- Try these fixes for can't use touchpad and keyboard at same time:
https://www.thewindowsclub.com/use-touchpad-and... (Avoid ad links which intrude into editorial copy, especially DO NOT INSTALL Restoro, PC Repair Tool and Reimage ads)
https://ccm.net/forum/affich-517036-touchpad-an...
https://forums.lenovo.com/topic/findpost/1092/4...
https://answers.microsoft.com/en-us/windows/for... (look for your brand touchpad in same registry setting)
- Update the touchpad driver from the PC or motherboard maker's Support Downloads webpage for your exact model. While there compare to make sure you also have the latest BIOS, Chipset, Display, Network and all other drivers.
If no newer then uninstall the touchpad driver in Device Manager, restart PC to reinstall it.
Next go into Device Manager, right click Sound controller driver to Upgrade driver, then Automatically.
If nothing newer found in Windows Update then try again but this time choose Upgrade Driver > Browse > Let Me Pick to try all previous drivers queued there.
- If none of these help then report back the laptop make and full model number, the touchpad make and model, driver version and date,.
Feel free to ask back any questions. Based on the results you post back, I will have other suggestions if necessary.
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