the "no internet" message is a Microsoft thing,
When a MS-client connect to a network, MS-Windows performs a reachability check to "connectivitycheck.microsoft.com"
if this check gets no timely response, it reports the status "no internet"
this is not necessarily your wireless network, it can also happen on your wired network
when the check has failed MS starts a back-off timer before this is tried a second time,
so it may be you can ping an internet host, but keep seeing the "no internet" warning
NB! it CAN mean your DHCP response or your authentication is too slow,
and some Microsoft process performs this check even BEFORE your network is fully active
and as @ahollifield says CoA may not work correctly
so you still need to investigate deeper
you can try to collect and analyze a wlanreport
open a command promt (as admin) and give the command "netsh wlan show wlanreport"
this will create a HTML file to analyze further,
details are better handled in a MS-windows forum than here in the Cisco Communities
