S4 Mini Fails to Start - Even After Factory Reset - failed to mount /efs I/0 error

A

AC Question

Hi all,

My S4 mini started doing some updates yesterday and it turned off while it was doing it. Now when I try to turn it on the Smasung logo appears but then the screen goes to black and doesn't get any further.

When I've put it in recovery mode I get the warning 'failed to mount /efs I/0 error'. I've tried deleting all data and factory resetting but this doesn't solve the problem.

Does anyone out there have any advice?

Thanks,

Stu