Comment 21 for bug 555571

My experience is exactly the same as comment 18

I quote:

I had this same issue after a reboot.

Ganton's post/link fixed it.

"I restarted my laptop because it could not be resumed: only a black screen with the shell cursor is shown on the top left."
"Network-manager-kde systray says that "network management disabled""
"This fixed my problem:
    service network-manager stop
    rm /var/lib/NetworkManager/NetworkManager.state
    service network-manager start
"