When running some applications (VirtualBox is one of them) I get the message
"Could not start process Cannot talk to klauncher: Not connected to D-Bus server"

when attempting an operation that opens a file picker.

I am running openSUSE12.2 on a computer that I upgraded from openSUSE 12.1. These applications all ran fine on 12.1. And also run fine for new users on 12.2. So I believe the problem lies with some .kde4 or .local or similar file - but I don't want to wholesale delete any of the contents of these folders as that is likely to stop something else working - like kmail or other.

Can anyone point me in the right direction?

Are these applications which are affected running under a different user to the user running the session?
Does it help if you erase /var/tmp/kdecache-$USER/ outside KDE?

No, the same user as the session.

I logged out and renamed /var/tmp/kdecache-djm as /var/tmp/kdecache-djm.old.

Unfortunately that didn't help.

The specific application that I most want to work but suffers this issue is VirtualBox. I know its not a KDE application, but it seems to be suffering a KDE infrastructure issue.

Can you please verify all files underneath your home directory are owned by your user?
In particular, focus on the ~/.kde4, ~/.config and ~/.local directories.
(find may be helpful here).

All files in .kde4 .config and .local are owned by my user.

I tried running VirtualBox as root and it works perfectly.

But I also created a new user, logged in as them and it doesn't work. Same issue.

Can you please verify that running "qdbus" produces a long output (with an ending similar to this):

Code: Select all

:1.76
 org.kde.kio_http_cache_cleaner
:1.8
 org.kde.bluedevilmonolithic
:1.91
org.freedesktop.DBus

I get...

> qdbus
:1.1
org.kde.klauncher
:1.10
org.kde.kglobalaccel
:1.104
org.kde.StatusNotifierItem-6036-1
:1.105
org.kde.StatusNotifierItem-6087-1
:1.106
com.Skype.API
:1.109
:1.110
org.kde.StatusNotifierItem-6034-1
:1.112
:1.113
:1.12
org.kde.StatusNotifierItem-5704-1
:1.122
org.kde.kio_http_cache_cleaner
:1.127
:1.128
:1.13
org.kde.kwalletd
:1.135
:1.136
org.kde.konsole
:1.145
org.freedesktop.PackageKit
org.kde.ApperSentinel
:1.147
org.kde.StatusNotifierItem-6989-1
:1.15
org.kde.kactivitymanagerd
:1.18
org.kde.ksmserver
org.kde.ksmserver-5717
:1.19
org.kde.kwin
org.kde.kwin-5720
org.kde.kwin.Screenshot
:1.2
org.freedesktop.PowerManagement
org.freedesktop.PowerManagement.Inhibit
org.kde.Solid.PowerManagement
org.kde.Solid.PowerManagement.PolicyAgent
org.kde.StatusNotifierWatcher
org.kde.kded
org.kde.keyboard
org.kde.networkmanagement
:1.20
org.kde.knotify
:1.202
:1.22
org.freedesktop.Notifications
org.kde.DeviceNotifications
org.kde.StatusNotifierHost-5738
org.kde.plasma-desktop
:1.24
org.kde.JobViewServer
org.kde.kuiserver
:1.27
org.kde.kaccess
:1.29
org.freedesktop.ScreenSaver
org.kde.krunner
org.kde.screensaver
:1.31
org.kde.NepomukServer
:1.33
org.kde.NepomukStorage
org.kde.nepomuk.DataManagement
org.kde.nepomuk.services.nepomukontologyloader
org.kde.nepomuk.services.nepomukstorage
:1.335
org.kde.apper
org.kde.internal.KSettingsWidget-kcm_apper
:1.34
org.PulseAudio1
org.pulseaudio.Server
:1.35
org.freedesktop.Akonadi.Control
org.freedesktop.Akonadi.Control.lock
:1.36
org.freedesktop.Akonadi
:1.40
org.freedesktop.Akonadi.Janitor
:1.41
:1.44
org.freedesktop.Akonadi.Agent.akonadi_contacts_resource_2
org.freedesktop.Akonadi.Resource.akonadi_contacts_resource_2
:1.45
org.freedesktop.Akonadi.Agent.akonadi_contacts_resource_1
org.freedesktop.Akonadi.Resource.akonadi_contacts_resource_1
:1.461
org.kde.akregator
org.kde.kaddressbook
org.kde.kjots
org.kde.kmail
org.kde.kmail2
org.kde.kontact
org.kde.korganizer
org.kde.pim.TransportManager
:1.463
org.kde.StatusNotifierItem-9622-1
:1.464
org.kde.korgac
:1.466
:1.47
org.freedesktop.Akonadi.Agent.akonadi_akonotes_resource_1
org.freedesktop.Akonadi.Resource.akonadi_akonotes_resource_1
:1.471
org.kde.StatusNotifierItem-9631-1
:1.472
:1.48
org.freedesktop.Akonadi.Agent.akonadi_ical_resource_1
org.freedesktop.Akonadi.Resource.akonadi_ical_resource_1
:1.49
org.freedesktop.Akonadi.Agent.akonadi_ical_resource_0
org.freedesktop.Akonadi.Resource.akonadi_ical_resource_0
:1.5
org.kde.BlueDevil.Service
org.kde.bluedevilfilereceiverhelper-5649
:1.50
org.freedesktop.Akonadi.Agent.akonadi_contacts_resource_0
org.freedesktop.Akonadi.Resource.akonadi_contacts_resource_0
:1.51
org.freedesktop.Akonadi.Agent.akonadi_akonotes_resource_0
org.freedesktop.Akonadi.Resource.akonadi_akonotes_resource_0
:1.52
org.freedesktop.Akonadi.Agent.akonadi_pop3_resource_5
org.freedesktop.Akonadi.Resource.akonadi_pop3_resource_5
org.kde.akonadi_pop3_resource_5-5867
:1.520
:1.521
:1.53
org.freedesktop.Akonadi.Agent.akonadi_googlecalendar_resource_1
org.freedesktop.Akonadi.Resource.akonadi_googlecalendar_resource_1
org.kde.akonadi_googlecalendar_resource_1-5855
:1.54
org.freedesktop.Akonadi.Agent.akonadi_nepomuk_feeder
org.kde.akonadi_nepomuk_feeder-5862
:1.56
org.freedesktop.Akonadi.Agent.akonadi_maildispatcher_agent
org.freedesktop.Akonadi.MailDispatcherAgent
org.kde.akonadi_maildispatcher_agent-5860
:1.57
org.freedesktop.Akonadi.Agent.akonadi_pop3_resource_3
org.freedesktop.Akonadi.Resource.akonadi_pop3_resource_3
org.kde.akonadi_pop3_resource_3-5866
:1.58
org.freedesktop.Akonadi.Agent.akonadi_maildir_resource_1
org.freedesktop.Akonadi.Resource.akonadi_maildir_resource_1
:1.59
org.freedesktop.Akonadi.Agent.akonadi_pop3_resource_6
org.freedesktop.Akonadi.Resource.akonadi_pop3_resource_6
org.kde.akonadi_pop3_resource_6-5868
:1.6
:1.60
org.freedesktop.Akonadi.Agent.akonadi_pop3_resource_0
org.freedesktop.Akonadi.Resource.akonadi_pop3_resource_0
org.kde.akonadi_pop3_resource_0-5863
:1.61
org.freedesktop.Akonadi.Agent.akonadi_googlecalendar_resource_2
org.freedesktop.Akonadi.Resource.akonadi_googlecalendar_resource_2
org.kde.akonadi_googlecalendar_resource_2-5856
:1.62
org.freedesktop.Akonadi.Agent.akonadi_pop3_resource_2
org.freedesktop.Akonadi.Resource.akonadi_pop3_resource_2
org.kde.akonadi_pop3_resource_2-5865
:1.63
org.freedesktop.Akonadi.Agent.akonadi_pop3_resource_1
org.freedesktop.Akonadi.Resource.akonadi_pop3_resource_1
org.kde.akonadi_pop3_resource_1-5864
:1.64
org.freedesktop.Akonadi.Agent.akonadi_pop3_resource_7
org.freedesktop.Akonadi.Resource.akonadi_pop3_resource_7
org.kde.akonadi_pop3_resource_7-5869
:1.66
org.freedesktop.Akonadi.Agent.akonadi_mailfilter_agent
org.freedesktop.Akonadi.MailFilterAgent
org.kde.akonadi_mailfilter_agent-5861
:1.67
org.kde.nepomuk.services.nepomukqueryservice
:1.68
org.kde.nepomuk.services.nepomukbackupsync
:1.69
org.kde.nepomuk.services.nepomukfilewatch
:1.7
org.openobex
:1.70
org.kde.nepomuk.services.digikamnepomukservice
:1.71
:1.72
:1.73
org.kde.kmix
:1.75
org.kde.nepomukcontroller
:1.77
org.kde.kgpg
:1.79
org.kde.StatusNotifierItem-6005-1
:1.8
org.kde.bluedevilmonolithic
:1.80
org.kde.StatusNotifierItem-6003-1
:1.81
org.kde.StatusNotifierItem-6007-1
:1.82
org.kde.amarok
org.mpris.MediaPlayer2.amarok
org.mpris.amarok
:1.84
org.kde.kget
:1.87
org.gtk.vfs.Daemon
:1.91
:1.92
:1.93
org.kde.Polkit1AuthAgent
:1.99
org.kde.klipper
org.freedesktop.DBus

Hmm, it seems you are able to access D-Bus properly.
I'm not sure why this is happening. Can you list applications other than VirtualBox which are affected?

I can't find another application that uses qt that suffers the same issue. So I believe it has something too do with being a setuid program.

If it is setuid then the environment is probably purged by the kernel, which means it is then likely either unable to authenticate to D-Bus or is living in a seperate session (but KLauncher refuses to launch - due to it already being running as that user). Not much you can do here as KDE was not really intended to be used in a setsuid application.

Same issue here, also on openSUSE 12.2 (manually installed KDE 4.9) and VirtualBox. Although it did work fine previously, when I used an upgraded system from 12.2 RC with KDE 4.8 and an older version of VirtualBox.

I would suggest filing a bug report with Virtualbox or your distribution. The quickest way to fix this would be by ensuring the Qt KDE Platform Plugin is not loaded - which means the generic Qt file picker is used instead, which should work properly.