I went off on my travels for a month leaving my laptop behind, My Daughters computer had problems so I let her use this machine on my desk with a USB mouse. Returned Fri and all was OK with this set up. Tonight I get ready to travel early tomorrow morning and found that when the USB mouse is removed the touchpad is not working. Tried Fn F7 and looked in BIOS nothing in to disable this device. In Device Manager > Human interface device this is only showing USB mouse. Tried add new hardware nothing showing. Any ideas before I make a idiot of myself returning it to the supplier. Have to be up early so might not answer later post till tomorrow lunch.
I think you are looking in the wrong place. My W7 Compaq doesn't show Touchpad in Devices and Printers either.
You will find it in Device Manager/Mice and Other Pointing Devices.
Note that I never use my touchpad, always a w'less mouse. But I was confused when I first got my laptop. Touchpad was enabled by default but then stopped working. After a few minutes I found that there is a flush tiny switch between the touchpad and the spacebar and I had inadvertently turned it off. Is Acer similar?
Anyway, I just turned mine back on, and it still definitely does not show in Devices and Printers.