So from your description, I am presuming that you have already gone through the standard recalibration:
Use the following steps to calibrate your touch screen in Windows 7:
If you have done this and the response has been negative, you CAN first try updating the touchscreen drivers from the hardware device manager. If that fails you can then try removing the touchscreen from the hardware device manager, rebooting, and letting Windows find it again.
That should reinstall/update the drivers.
If none of THAT works, then it may be hardware related. If it is hardware related, and the unit is still under manufacturer's warranty, you can call Acer customer service here: 1(###) ###-####
You tried all three things I suggested?
If so, then the only thing you are left with is going to Acer to see if they can get someone to look directly at your touchscreen. They DO fail in strange ways. I have a Sony Vaio touchscreen that only failed on the right side. I wish there were more to suggest, but barring a complete system reload, this is where we are.
I am sorry. I wish there was something else I could do for you here. But with hardware being the likely culprit, there is very little anyone could do in a venue like this.
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