This is a trick if you want to reset your firmware without factory reset. So you can keep your data, but using this method will remove your custom recovery, root and other modification in your ROM
Preparation
- Download ASUS Zenfone Stock Firmware that you right now (in this post, i make example using Firmware UL_ASUS_T00F_WW_1_18_40_9.zip)
Zenfone 5 stock ROM without Upgrade / Downgrade
- Extract your firmware until you find UL_ASUS_T00F_WW_1_18_40_9-user.zip
- Rename UL_ASUS_T00F_WW_1_18_40_9-user.zip to UL_ASUS_T00F_WW_1_19_40_9-user.zip
- Connect your device to PC /Laptop
- Copy UL_ASUS_T00F_WW_1_19_40_9-user.zip to ASUS Zenfone 5 internal memory
- Remove Zenfone 5 from PC / Laptop
- A warning window will appear and said a new update firmware is available, select and OK
- Wait until update process is finish and reboot your device
- Done
note: the trick is only rename the firmware, so system tought that a new update is available.
Do With Your Own Risk