So first and foremost,im no expert with this,but here are my suggestions from what ive been reading.
The nv_data files are generated by the android os.
So this assumes you have no backup of the "/efs" folder.
Get ODIN,and download the stock MF9 tar file,i believe theres a listing for the files somewhere in the development thread.
Rooted or deodexed,you choose.
From what ive gathered,youre gunna need to reflash(with Odin) the stock firmware,and it "should" regenerate those files.
The Stock MF9 TAR file should be about 1.4 GB in size and ~2.x GB after extracted.if youre unfamiliar with how to use Odin,let me know ill walk you through it.
Before following through with all this,BE SURE to backup music,Pictures Etc,to your EXTERNAL SD card or better yet your PC.ODIN will reflash EVERYTHING.including your internal sd,so if you have anything there youre gunna want to back that up too.
In the meanwhile,
Read this.its for an S2,but the same concept applies.
iPhone 4S 6.1.3
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