Maybe it's soft bricked.
Using odin to get you into download mode (not recovery), and flash a stock .tar file to get up and running again. Unless you have a hardware issue inside the phone.
If you want a decent tutorial on doing this, YouTube search "unbrick i717 odin" and the first video listed (for me anyway) is a video by Qbking77 on how to do this step by step. He gives links to odin files and .tar stock files for the i717.
A little under two months ago, AT&T started rolling out … more
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