Hi,
Did you get any error message when you tried to install the Touchpad driver? Also did your laptop really has Synaptics driver for your touchpad, there's 2 driver available in Acer Support site 1.Synaptics 2.ELANTECH.
- Go to Device Manager and check what really is under Touchpad driver.
- Uninstall it and reboot your laptop and it should reinstall automatically.
- If it doesn't install download and install the latest driver from Acer site.
Synaptics:
http/global-download.acer.com/GDFiles/Driver/TouchPad/Touchpad_Synaptics_18.1.47.31_W81x64_A.zip?acerid=635651786265578929&Step1=NOTEBOOK&Step2=ASPIRE&Step3=ASPIRE%20E5-573G&OS=81P1&LC=en&BC=ACER&SC=PA_6
ELANTECH:http
/global-download.acer.com/GDFiles/Driver/TouchPad/touchpad_ELANTECH_13.6.1.1_W81x64_A.zip?acerid=635651785852688929&Step1=NOTEBOOK&Step2=ASPIRE&Step3=ASPIRE%20E5-573G&OS=81P1&LC=en&BC=ACER&SC=PA_6
- Reboot your laptop once the latest driver has been install then test it.