Try reinstalling the touchpad driver:
Firstly you'll need to know whether your machine has an Elantech touchpad or a Synaptics one. (Acer used both in the AO722). You can either seek the information from the Device Manager (via your Control Panel) or you can download and run this file to give you the same information:
http://global-download.acer.com/SupportFiles/Files/HWID/APP/HWVendorDetection.exe
If it's a Synaptics touchpad you'll need this file:
http://tinyurl.com/jpmcoz3
If it's an Elantech one you'll need this file:
http://tinyurl.com/jaraofz
Download the touchpad driver installation file.
Double-click on it to run it.
Restart your machine.
Cross your fingers!