I've got a T420 Lenovo laptop running Windows 7 prof. I also have a Samsung Galaxy Tab 2. The Chromecast is up and running fine on the tablet and my wi-fi network. But it won't work on the laptop after setup. The laptop is on the same wi-fi. I have checked that the software is up to date, I have the Chrome Browser extension. The Chromecast icon doesn't show up in YouTube, and in the Chrome browser, the icon is there, but shows No Cast Device Found when I click on it. I don't have a Netflix account. I have Avast antivirus running and just the Windows Firewall. I think I had both of them off unless there's some trick I'm missing, and that didn't remedy the situation. I tried the various reboots and restarts, etc, to no avail.
Anyone have any suggestions? I've been reading your threads and you guys are a lot more techie than I am, but I'm willing to try things!