My AP (routeur) is just close to my ALFA network adapter (AWUS036H) !!!
I tried with Network manager and WIFI Radar = I can associate with APs but cannot get an IP adress. SO the DHCP step fails ... in every case ...
But i can inject, the network is started ... the ALFA card is recognized by system (rtl8187 driver is loaded)...

Would it be a DRIVER issue ??????

When the access to AP is open (no WEP) it works ...

Than you for helping me, i made so much reserches ... without any answer ... or track ...