mobile

hi friends
LG G3 D855 - Android 5.0-ROOT

I want to install the CUSTOMROM. I installed TWRP. I restart the phone, I see Secure Booting Error! Cause: boot verify certification.

Then the phone turns off, the warning light starts to burn ...
I wear again, remove the battery, the phone works.

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I want to Twrp to install custom ROMs ..

1. I installed Kitkat
2-Root
3-I installed TWRP.
4-Phone I rebooted, it s work for the ... (TWRP working)
5-. I install custom ROMs and bump with TWRP
6- I restart the phone, I got the error again (Secure Booting Error! Cause: boot verify certification.)
I restart the phone, remove the battery, but I always get the same error.

I install android 5.0 with Lgtools, phone is working. But I want to install custom ROM. How do I make