the author of this app says:
For Samsung Galaxy S II
Use it only on Galaxy S II, this apk format "/dev/block/mmcblk0p1" for repair it.
I am not responsible if you use it on your phone and brick it.
If your sim card is not detected, no signal or your efs folder is blocked on read_only, this apk help you.
Need root and busybox
Include save/restore efs folder
Don't contact me if this method not work and if your phone need repair.
If you use this program, your phone don't work and need any repair, this is your last chance for repair it without samsung.
I have made this program because it repair 9/10 phones with the no sim-no signal problem.