Ubuntu server installation help

[Ali_Qudrat]

hi so i basicaly thought i was smart in computers until i tried installing ubuntu server :( i wanted to install it to run a minecraft server anyways why computer connects with a wireless card and during the installation im having trouble at the configure the network part. I choose Wilan0 and then i type my wireless name and then i do wpa/wpa2 psk and then i type my password but it all ways says
Attempting to find an avaliable wireless network failed etc... please help as i have been on this for days and i have tried everything else but i cant find a solution.
Thanks in advance