If you notice any software malfunctions with your Vivo X5 Pro android device, you're most likely required to download and flash stock ROM firmware on your X5 Pro to permanently correct the software errors you noticed on your Vivo X5 Pro. And when you load stock firmware on your Vivo X5 Pro using any Qualcomm flash tool, your Vivo X5 Pro will be reset to factory defaults settings and by that, definately, your UserData will be lost including contacts, messages and others.
If your device has been bricked and want to unbrick it, you will need to pay closer attention to the tutorials contained below here.
Vivo X5 Pro Stock ROM Firmware Download Link(s)
1. Vivo X5 Pro_PD1421F_EX_B_3.8.2
2. Vivo X5 Pro_PD1421F_EX_B_3.8.11
How to Flash Stock Firmware On Vivo X5 Pro
1. Download your Vivo X5 Pro stock ROM firmware from the link above.
2. Extract the Vivo X5 Pro Firmware you downloaded from the link above onto a folder on your PC.
3. Download and install Qualcomm android device drivers on your PC. You may skip this step if you have installed Qualcomm drivers on your PC already otherwise, download Qualcomm drivers here
4. Now, choose either of the tools listed below here to load the stock firmware on your Vivo X5 Pro.
Note
1. Each of the tools listed above contained step by step guides with illustrated pictures on how to flash stock firmware on your Vivo X5 Pro.
2. If your device is bricked already, I recommend that you use Tool Studio eMMC Download Tool or QPST QFIL.
3. If you require any further assistance, simply drop your comment detailing the issue(s) and I shall help you revive your Vivo X5 Pro, if need be.