I'll be as specific as possible. I have wireless att dsl at home. I can obviously access this site and instantcert but instantcert will not let me login with my dell laptop. When connected to my home wifi with my iPhone 4 I cannot login. When I turn off the wifi and use my 3g connection I can login just fine with the iPhone. I went to the contact us webpage and submitted a form request but am afraid to wait the 24 business hours for resolution unless all else fails.