I would suggest calling Sony or taking it back to the man you bought if from. If it's not the FN button issue it's probably just plain broken. Since it's new hopefully they will fix it or replace it.
You need to connect a mouse to it to check if the "built in pointing device" has been disabled in Start, Viao? Support Central,System maintenence,viao central,system information
Click the + next to keyboard and mouse ad double click on the "built in pointer" icon
If the Enable button isn't checked then that is the problem, click in the box to enable touchpad then save the settings by clicking ok then verify the changes with yesf needed
I just had that issue with my laptop.
You need to get into your control panel by pressing the windows button.
Use the arrow keys to get to the mouse icon and press enter.
Once in mouse properties press control and hold it while pressing the tab button.
Tab over to device settings tab. Release the control button.
Now press the tab button and tab to the settings button under the device settings tab. This should take you to an overview screen.
Now use your arrow keys and arrow down to the tapping area.
Press the tab button and it should highlight the enable tapping area.
Press the space bar and it should place a check mark in the box.
Now press the tab button until the apply button is highlighted.
Press enter and you should be good to go.
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