this is my keychain settings....
its not only the network settings but the keychain Control Access settings too, in keychain go to your keychain app>double click on your system keychain and you should have your wireless network there or in your user or login section, the following files should be in the list in the access control tab: system preferences, airport, systemUiserver, apple80211Agent mainly. Also in your network setting under the proxies tab in the field called:bypass proxies for these domains and fields, you should have the name of your computer: your computer name,169.254/16. also in the sharing pane the name of your computer must be registered in the field required.
If your keychain is only in your system section find a way of copying it over to your user section and your login section, so its in the three sections, if you cant drag it over just make one manually and input the same information as much as you can.