► First we need to know what is FRP lock?
Factory Lock Protection Lock (FRP lock) is a type of security lock similar to Apple iPhone and is only available on Google's Android 5.1.1.
► FRP lock occurs when you are logged in to a Google account and has Secure your machine with one of the following methods: password, pattern, fingerprint ... and your device will lock when you restore it with Recovery or when Root the machine then FRP LOCK will activate.
❄ How to disable FRP Lock directly on your device?
► FRP Lock is a security feature of Google when you turn it off means your device will not be high security if you want to disable this feature you just
★ Open => Settings => Phone information => Click 7 times continuously in the Build number, or Build number => Press return and select => Developer settings => Enable ON (OEM unlocking) => If the machine asks for a password, press Enter your password and select yes => so your device will not be FAP LOCK anymore.
FIX with box with version or model support, this fix you will not lose data. The machine will return to normal. Of course, for those of you who do not have a box, this is a pretty hard way, because of personal data, you can bring it to the store or ask for a box to try to save the data instead of the original flash will be lost.
With the model and version that support box, just bring the machine to Download Mode. Connect usb and press reset frp / reset ss on BOX. The boot machine is back to normal
If you remember the exact model then download the original rom on sammobile or other webs with the new version must be equal to or greater than the current version. Shut down and put the machine on DOWNLOAD MODE and run through Odin, the machine will boot into normal, then you log in with the previous tk was used is done
Use Odin software to run SAMSUNG software here
If you do not remember the model, when you enter DOWNLOAD MODE you can easily identify the model of the machine
If the machine after the flash finish but can not boot to normal, or hang and then boot, you put the machine into RECOVERY mode and select WIPE FACTORY RESET / WIPE CACHE and the machine will boot normally.