alienware m17xr3 touchpad button

You can try to uninstall the touchpad driver and reinstall it again, as well try to perform a power drain and if the issue persists you can flash the BIOS  to the latest version you find in the Dell support site. 

hi i had already flashed the bios, i am unsure as to which driver it is for the touchpad r289408 or r289406, is a power drain removing ac and battery and holding power button for 30 seconds thanks

This one: Synaptics Touchpad Driver.

hi thanks for the information unfortunately the driver hasnt changed the problem though, bit of a pain

I will recommend you to test it on safe mode and if the issue persists then it should be a hardware problem.

ok  so it does the same in safe mode, is it likely to be the button or is there something else it could be

Then yes you should be facing a hardware issue and the only way to fix it will be with a replacement. 

could it be a board or anything other than the actual touchpad

There are few possibilities that the motherboard is the one damage that is why I will recommend you replace the touchpad first.