Correcting WAN miniport devices on windows 8.1

Since I upgraded my system to windows 8.1, I continuously get the problem of VPN not getting connected due to corrupted WAN mini port (Indicated by yellow exclamation mark in Device Manager).  This lead my formatting my system couple of times but finally I able to find the resolution. Please perform the steps below:

1. Open Device Manager.
2. In network adapters section, you will find WAN mini port devices (IP, L2TP, PPTP).
3. You can observe the broken mini port my observing the yellow exclamation mark in front of them. 
4. In case WAN mini-ports are not listed try by selecting the option “See hidden devices” from menu.
5. Got Registry editor and browse to HKEY_LOCAL_MACHINE -> SYSTEM -> CurrentControlSet->Control->Class->{4D36E972-E325-11CE-BFC1-08002BE10318}
6. Go through each of the sub keys to find the sub key corresponding to the broken mini-port. This information can be seen in the DriverDesc value.
7. Once you got the key corresponding to broken mini-port, delete the sub key.
8. For reinstalling the WAN mini-port go to Device Manager.
9. Select broken mini-port.
10. Right click the selected broken mini-port and select ‘Update Driver Software’
11. On Next screen select the option of Browse my computer for driver software.
12. On Next screen select the option of ‘Let me pick from a list of device drivers on my computer’
13. Select the only network adapter listed there and click next.
14. After successfully installing the driver you will observe the yellow exclamation mark is gone in device manager and mini-port is fully recovers.
15. Repeat the steps 9 to 14 for all the broken mini ports,