Hi, welcome to iPadForums!
If you haven't seen this yet, try the solutions on the following site:
https://support.apple.com/en-gb/HT204291
To which device do you wish to connect your iPad via AirPlay?
Just to make sure:
Reflector is installed on your PC? You accepted the EULA when installing it? It's allowed through Windows firewall (public and private networks)?
I assume your iPad is capable of AirPlay (iPad 2 and later).
If it's like the one in your link, it's an iPad 4.
What about Windows Firewall?