Some computer manufacturers have a BIOS update that addresses this problem, so I would suggest updating that first.
Then, make sure your video card drivers are up to date. In many cases, this will resolve the issue, and the TV will see the input.
I have a Samsung TV and a Sony laptop. When I connect the Laptop to to the TV via a VGA cord, I am not given then option of PC on my TV. What settings must I have on my laptop to make the signal work? Is there any specific drivers that I must have loaded on my laptop?