LAN can be exposed to a double Wammie!.......Lightning strike can hit not only your house power, ... but down telephone lines too
No experience with testing whether its fried or not, but lucky you have a second port to keep you up and running
The value of a "Good" spike protection in your system come to mind........a good quality power filter board will carry both power and phone jacks for this very reason.....As do UPS units if you have the Money.....or better still , ... "Both"
I don't really believe in co- incidences ... PC problem....+.....electrical storm...+..zero power protection = one LAN ..... very lucky really,...could have been the entire rig!
Now that out of the way.......The only thing I can think of is, .... download the driver concerned and pop it on a pendrive....download something like Revo-un-installer and install........next turn off machine and configure hardware to trouble port and reboot to windows.........us the un-installer at it's deepest setting to rip out the driver and all sub folder applicable and reboot if you have too..........install drivers again and reboot to windows and see if it's back!
Aussie Allan