Can't install OF1 even after root is removed.

I wanted to update my phone to OF1 but every time I try to update it says that the update failed. I tried Uninstalling root using super SU and root checker claims that root is no longer installed however every time I boot it does that black screen with the word "custom" on it. Is their a way to make it so that I can accept the OF1 update? (Especially since I just learnt of stage fright which that is supposed to fix).

Sent from my SCH-I545 using XDA Free mobile app

Removed OS, Cannot reinstall a new ROM.

Hello

First of all, let me explain the situation:
My phone is the Oneplus One, currently with no OS, the reason being - because i wanted to re-root my phone after the Oneplus updated (this update was a while ago) either way many problems occurred and i figured the easiest way to re-root my device is to simply wipe it, and try again on a clean slate.
I attempted to wipe my phone, but did it the complete wrong way. Instead of using the OS's wiping strategy, i may of used the recovery's one instead, doing so i clean swooped the OS right off my phone.
At the moment, the phone has no OS installed - nor is the phone rooted. The phone isn't capable of passing files over through usb debugging because the computer doesn't recognise it no more. (It did have usb debugging turn't on). Of course i need to reinstall an OS on the phone. The TWRP recovery is working fine. But i do not know how to do it. I looked up things such as mounting, didn't really understand the vague explanations given by the helpers of this forum (i am slow haha ). If someone is able to point me in the right direction in how to simply put an OS back into the phone some how i would be grateful.

I did read up on one post that suggested making a system.img placing the OS inside and flashing it over using fastboot mode. Which brings me to the question. Is it possible to use command to install an OS on my Oneplus whilst in fastboot mode?

how to install stock browser on custom rom that removed it

I installed this Rom on my s6 that is debloated with everything removed and I love it, but I do not have the stock browser. I do I install the stock browser on my device?

"CHECK BATTERY COVER" AND "SD CARD IS REMOVED" issues.

Hello everyone. I getting some problems on my S5 mini G800F .
When I bought it, worked perfectly, but then some days later a very annoying "Check battery cover" popup is coming up, when I restart and when I wake up and unlock my phone. And it got even worse. When I woke up my device, it comes with that annoying msg but it stands for 2 seconds and U CAN'T CLOSE IT! I PRESSED FOR 5 MINUTES STILL IT DONT GO. I FIGURED OUT THAT ONLY WHEN I PRESS MULTITASKING OR HOME BUTTON STOPS THIS. ONLY FOR THIS TIME. Then week later, a "SD card is removed" error comes up :mad: . I formatted it on my phone. What is the problem of this? :what:
EDIT: RESTARTED MY DEVICE. AND I GET ON BLACK BACKGROUND POPUP "CHECK BTR COVER" AND U PRESS AND IT DONT GO. BUT IF I PRESS HOME IT GOES AWAY BUT TOUCHWIZ LOADS LIKE IT WAS CRASHED OR JUST STOPPED. WHAT IS GOING ON WITH MY DEVICE?? :( :mad:

Avengers themes are being removed from theme store?

Hi guys, today I tried to install avengers theme black widow but I can't find that theme anymore actually all avengers hero themes are removed. So is it just me or all see this? Also anyone can help me get this theme for my galaxy s6?