problem to read surveillance cameras from my ipad

dHello

It is my first day on the forum.

I have a surveillance installation since two yeaurs.

There are 4 cameras connected on a Hikvision DVR VED-7200 HWI-SH

The video recorder ha a coaw-connexion to the television-providing box

I consult the images via my personal computer, and WIFI-connection to the television-providing box.

Everything OK since two years

Since some days I switched to an ipad air2.

I have put the iVMS-4500 HD soft on the ipad, but I can not have a connection with te video recorder.

I had some tries with exactly the same adresses as on the PC, but no way to fix it .

Anybody with suggestions ??

Thanks

Eric