ipad blocks inteet access for all other devices

I have a TP-Link WR841N router. This seems to work fine except that when a specific ipad is connected to the wireless, it can access the inteet ok but no other devices can. There is no problem when iphones or other computers are connected. All devices can always still connect to the router.

The actual network setup is a bit more complicated. The router is plugged into homeplug adaptors, which are then plugged into a etheet port which forms part of a school network (we are teachers in a school house). The school network uses some kind of web authentication. The first time an etheet cable is plugged into the school network, one of the computers needs to go through the web-based authentication, but then after this the authentication seems to cover all computers and doesn't need to be re-entered unless the cable to the school network is removed.

I have tried installing dd-wrt (now installed and working ok) but this did not solve the issue. The ipad is a school ipad whilst the rest of the devices are not, and I thought this might have something to do with it, except that I had understood that everything behind the router would effectively be invisible to the wide area network. I have tried bandwidth restrictions for the ipad but this has no effect either.

Any help would be greatly appreciated.

Recent Questions...