Hi Louis,
This is a difficult sentence, because you use no points or comma's ...
I am no expert, but it sounds to me like something went wrong during install or update.
Unless you report that previously you did not have this problem.
Maybe answering these questions could give more insight to finding a solution:
Were any error messages reported during install or update ... ?!?
Did you confirm that there is no driver problem with your NIC ... ?!?
What type of NIC are you using ... ?!?
Did you try to replace your NIC ... ?!?
Anyway ... that's all I can think of right now.
Good luck,
John