As most OnePlus fans would know, the OnePlus One smartphones come pre-loaded with CyanogenMod 11S ROMs after they struck a deal. That doesn’t mean you are restricted to using the CyanogenMod ROM, though, as many third-party developers have created other custom ROMs available for the popular handset. If you are one of those people who opted to get away from the CyanogenMod ROM and wish to return back to the stock version how it came out of the box, you can do that by following the steps below.
BEFORE WE BEGIN
- You need to download the latest version of Java from this link  on your computer. Choose the correct operating system from the list.
- You must download the OnePlus toolkit from this link  to the desktop of the computer.
- See to it that you enable the USB Debugging Mode from the Developer Options menu.
- If you cannot see any Developer Options menu from the phones Settings menu, you will need to lock it by going to the “About Device” menu and then tap the device build number for at least seven times. The About Device is also available after tapping the Settings application on the smartphone.
HOW TO FLASH THE STOCK CUSTOM ROM CYANOGENMOD 11S ON THE ONEPLUS ONE
- Have the toolkit running on the desktop of the computer.
- Choose the option that says Enter Fastboot/Recovery Mode.
- Click the mouse over the Flash CM11S option.
- Now the toolkit will do its thing and begin to flash the firmware on your device. Do not touch any buttons until it completes.
- Return to the app drawer and verify that the SuperSu application is no longer there. It may take a reboot before that happens on your handset.