What browser are you using to go online with? shouldn't make much difference, but sounds like you need to make sure your Ignition Key has the authorisation licence made 'active' so you can use 'offline'.
Go to 'Your Products' and 'Manage Licence'. The browser will look for your key in the USB, when it finds it, it should replicate to the IK.
If you still get stuck give us a shout back here
if it's a faulty Ignition Key, then speak with Props so they should send you a replacement one. What system are you using? Mac or PC?