1. From network system tray icon menu choose "Configure Network Connections...". 2. Select a wireless connection and click "Edit". 3. KDE shows warning popup that "No agents were available for this request". 4. Go to "Wi-Fi Security" tab, enter password and click OK. 5. Go back to step 2 and warning shows up again and password field is empty! In general configuration I have selected both: + Automatically connecto to this network when it is available + All users may connect to this network KWallet is disabled. I have had this problem already for several Kubuntu versions.
If you expand the width of the dialog you will see that there is a save button icon you can click to save the password for all users.
Ryan P.C. McQuen thanks for this tip. Perhaps the UX can be a bit better there. I had two icons behind each other in default window size. Why password only saves when I save it for all users? If I save it only for my user then when I reopen this dialog right away the password field is blank.
Checking "All users may connect to this network" doesn't save the password for all users anymore as it was before, now you have to do what you write above. If you don't have KWallet enabled and you store your password to your current user then it won't be stored at all and that's why you are getting "No agents were available for this request", which means that NetworkManager were unable to retrieve the password for your connection. You either have to enable KWallet or set that the password will be stored to all users (unencrypted).