This is an intermittent issue I am experiencing. I have taken a packet capture using Wireshark on both a defective machine and one that works. Bascially, what I see is the Supplicant does not send an EAPOL-Start and therefore authentication does not begin and no DHCP address is assigned, hence no wireless connectivity. I see this on all models of Dell Laptops. Anyone see this behavior and know a fix. I can find nothing on the internet except a registry fix. Also, areas of the building are worse than others. Unfortunately, I do not have access to the APs and cannot provide IOS rev. information. These are Cisco Aironet 1100s. Any help is very much appreciated.