RE: Apple IPAD cannot access to internet, captive portal
It depends on the reason for the page being blocked.
' Allow' only allows the site for that SPECIFIC check. (ie: Web URL filtering, but not FortiGuard category filtering).
Depending on what you have enabled it could be getting blocked by a different check.
Check the logs to find out what exactly is blocking it, and why. The allow it where it is blocked.
You could also use an EXEMPT action, but that would bypass ALL further checks and my not be what you want.