I am in the exact same circumstance; and i've never rooted it. All of a sudden it began to boot loop. The thing is -- is that I have data on there that I really need to preserve. Is there any way that I can reach the data on the hard drive? I've done a wipe cache partition function.
I'm also receiving some of the following error messages (among others):
failed to mount /efs (Invalid argument)
E: failed to mount /data (Invalid argument)
can't mount '/data (Invalid argument)
Please advise if you're familiar.