Network cable not detected by Windows Vista

weird one this one ,when plugging in the network cable the system doesn´t recognise it and says no network devices available to connect to.
Also the wireless adapter connects to a network but gives an error saying that it cannot get Internet access.
First thing to try is make sure they are fine in Device Manager If they are then we try uninstalling both adapters from Device Manager ,reboot and test again.
If the problem persists then disable the firewall and Anti-Virus program and see if it will detect the cable or connect to Internet.
Since I was getting errors saying that the firewall could not be enabled and the network service could not be started I decided to rather repair the Vista installation using the Upgrade Option Of The Vista DVD as it installs vista on top of itself and repairs any corrupt system files.
no information will be lost too, here is complete instructions ; http://vistasupport.mvps.org/repair_a_vista_installation_using_the_upgrade_option_of_the_vista_dvd.htm