I would try plugging in the HDMI cable to your TV/Monitor and laptop, making sure their settings are correct and set to the proper HDMI port and switched on of course. On the laptop right click desktop, personalise, display, change display settings, then click on the Detect tab. On that page you can also choose which displays to have. It will only work if you've connected to, say, port 1 on the TV/Monitor and the TV/Monitor is set to HDMI 1. See if you can get it to recognise the Monitor/TV that way.
Otherwise you might need an Intel driver update. Intel® Driver Update Utility