So on my friend's desktop, he wanted me to update his Windows 8 to Windows 8.1. So we went on the store app and installed.

After all the process, we type the password to the computer and then after loading the desktop, there is a screen saying that there is an error:

BUGCODE_NDIS_ DRIVER. and tells me to look online later. After this message, it has a % that goes up to 100% and restarts my computer. It repeats over and over. What do I do?