01-15-2016 04:50 PM - last edited on 01-23-2016 07:50 AM by Majestic
for ideapad 100 users who has sentelic touchpad, to make all gestures incl 2 finger scroll work, do following
download synaptics driver - http://www.synaptics.com/en/drivers.php
disable driver signature enforcement (this is slightly unsafe, read about risks and decide for yourself)
then unzip and install driver manually through device manager:
open ps/2 compatible mouse device
Go to Driver tab and select Update Driver
Select Browse my computer for driver software
Select Let me pick from a list of device drivers on my computer
Select Have Disk...
Select the extracted driver folder
agree to install driver without digital signature.
after reboot synaptics icon will appear in the tray, and all gestures will start to work.
to lenovo rep: win 8.1 and win 10 driver for ideapad's 100-15iby sentelic touchpad could not be installed correctly, after install and reboot sentelic tray app closes itself. this is why scroll doesnt work.
driver downloaded from windows 10 auto update also has the same problem, because it is the same driver which is available from lenovo ideapad's 100-15iby support page.
so do your work and tell those dumb driver programmers that they need to fix this sh1tty driver or to ask synaptics to sign generic one for them.
this is only lenovo's fault for supplying driver that doesnt work.
sentelic touchpad itself are near-clone of synaptics touchpad, and has all multitouch capabilities of it(3 finger). with correct driver it works out of the box, you can witness this in linux.
Mod's Edit: Marked this posting as the Solution since is has verfied responses that it worked.