The key is use itunes to restore it.
1. Open Itunes on your PC (you've use the latest version itunes 12.3.3)
2. Turn off you ipad & then turn on by pressing "home" & "power" button at the same time. After the apple logo apper, release power button BUT keep hold your home button. you will be ask to connect your ipad to itunes using cable data.
3. choose to restore, your itunes will be download ios 9.3. let it download.
4. error message maybe appear saying your ipad can't be verify, just leave it untill itunes finish download 9.3 ios (at top right conner has download progress).
5. After finish download, repeat step at no.2 this time itunes will start restore your ipad.
6. after restore finish, follow the instruction step & you'll be allow to choose "start as new ipad" or "restore from your last back up" it's up to you to choose, it only restore your songs, movies, & app. your ios allready 9.3
Hope you'll get your ipad running again.
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