How to disable root access in my Lumia 521?

[nitikosovo]

Hello I just followed this guide - http://forums.windowscentral.com/wi...-redstone-unsupported-devices-x2x-series.html
I am in Editing Registry Keys = Step 3 When i should disable root access -
I click Disable root access but everything it does it's that reboots in mass storage mode and it says like that !
I press Power+V- Button and it restarts the phone but still when click in the menu Disable Root Access it still shows me the option to Disable Root Access ]
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Please help me what should i do!!
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Edit - Guys sorry i bothered you , i just restored the bootloader without giving a **** for wp internals showing me the option to disable root access now it is downloading Windows 10 Update btw thanks Conan-
I will update you when the updating is finished!!