do you have any backup of previous roms or atlest your EFS ??
If you have flashed the rom from Philz or CWM recovery then there are high chances that the developer have used the option of "Backing up EFS" and it might be on your sd card..
Please share what have you done so far with your tab.. if you got no backup of EFS then forget about calling functions of your tab .. All i can help without the EFS backup is in restoring your tab back to its normal state..
go to sammobile.com download your ROM from there :
1) Go to sammobile
2) Register and sign in
3) Go to firmware section
4) download the P3100 rom of your location ..
5) Flash it with odin with "Phone EFS clear " option UNTICKED
You might have ticked that option and your EFS got cleared .
Efs holds the imp data like IMEI numbers .. which is illegal to fiddle with in any country..
More info here : http://rescueroot.com/android/how-to...msung-devices/
and here : https://play.google.com/store/apps/d...oris.efsbackup
AND THIS IS THE DANGEROUS ONE:
Do this only if you are little expireinced in rooting and stuffs ..
and i hope next time onwards you will be carefull to backup your EFS