Well something is blocking the traffic... you have to check between the wireless vlan and between that server...
Also the same thing must be blocking for the windows activation...
IF you want to prove to your client that the wireless is not the problem do this
Trunk one of the wired vlans to the wireless controller
On the VAP change for min the vlan of the wireless you using for a wired one you know its working...
Connect wirelessly, and everything should work correctly...
Remember to put it back again like it was because using a wired vlan for wireless is not recommeneded
Or you just can create a new SSID put a wired vlan and test... and then put the wireless vlan and test...
Cheers
Carlos