Your processor certainly has support for VT-x, but this doesn't necessarily mean that your laptop has support. The feature is enabled by the laptop's BIOS. If the BIOS it does not enable support, it isn't going to work. Can you verify that the feature is enabled once you are in your O/S?
You have to look in BIOS Setup for the enabling parameter. If you cannot find one, there is still the possibility that the laptop enables it regardless. Either way, run a tool that checks and displays whether or not the virtualization capability has been enabled in the O/S. If not, you will have to contact your laptop manufacturer to find out if an updated BIOS is available that allows for this capability (presuming they will even talk to you about a laptop this old).