Son Rooted Galaxy S7 (SM-G930P), Trying to Unroot with No Luck

[AC Question]

So my 15 year old son decided it would be great fun to root his phone. Problem is, he's not one for details so he miss the warning that said "this is old...it doesn't work...don't do it".

I've rooted a couple phones many moons ago but it's been a while. I've tried flash using a multitude of "restore factory firmware" sets of instructions but every time I do, I get "an error has occurred while updating your device's software".

I'm afraid I probably already know the answer to this question (and I've looked on this site as well as others), but can anyone point me to a resource that is known to work? Or are we stuck with an expensive paperweight?

Thanks in advance.

 

[smvim]

Yeah, it sounds like you really need to just re-flash to a stock ROM and get your S7 back to it's original state.
Here are a couple of links for S7 ROMs for your model, both the sammobile and updato sites are repositories for verified Samsung stock ROMs.
https://www.sammobile.com/firmwares/database/SM-G930P/
Download Firmware – Samsung Update
Note that its really vital you use the specific ROM that applies to your specific model/carrier/locale. Don't try to use a substitute, ROMs are not interchangeable at all.
This link has a run-down on how to use the Odin utility to restore your ROM:
https://www.androidsage.com/2016/03...galaxy-s7-and-s7-edge-full-firmware-download/
You can use the ROM listed in the article or use one of the sites above, as for the Odin utility use the version shown in the article. Newer versions often have issues with newer hardware. Also, if you already have Samsung Kies on the computer you're using you might want to uninstall Kies (leaving the Samsung drivers installed) as some people have reported conflicts between Odin and Kies. You can download Odin from here:
Download Odin (All Versions) for Samsung Galaxy Devices
If you don't have access to a Windows PC (Odin is Windows only) you can use an Open Source alternative, Heimdall (there are Linux, Mac, and Windows versions):
http://glassechidna.com.au/heimdall/