An innocent update this weekend to my Fedora 15 (KDE) system broke the Wireless Connection. The culprits – NetworkManager 0.8.9997-4.git20110620.fc15 and NetworkManager-glib 0.8.9997-4.git20110620.fc15. To make matters worse, anything I did within Network Manager crashed Plasma.
To fix this problem, I first setup a wired connection and then reverted both packages to their previous versions 0.8.999-2.git20110509.fc15, using this command
yum downgrade NetworkManager*
There is a forum link here which discusses this problem.
The official bug report: https://bugzilla.redhat.com/show_bug.cgi?id=716591
B Space 
Pingback: Links 28/6/2011: Android Activations Surpass Microsoft Windows, Millions of OLPC XOs Noted | Techrights
I hope they fix this soon. I don’t have a wired connection so I’m using a live cd to connect to the wireless signal and is really annoying.
I agree. I am checking everyday if a fix is out.
Did they fix it already?
Yes, I updated today and the problem is gone. Updates to a few plasma packages were available and could have fixed the problem. I did a “yum update” rather than rely on KPackageKit. KPackageKit did not show all the updates 😦
I had this problem too. I was about to follow your instructions to downgrade, but decided to check the updates. There is an upate available that fixes it – worked for me anyway.
It seems it was an issue with an old version of ‘kde-plasma-networkmanagement’ and the new ‘NetworkManager’ (nm 0.9). Upgrading kde-plasma-networkmanagement is supposed to fix the issue. Comment #6 on this bug report explains it so.
Yes, that is what I did. See my comment in response to ladiesman217