Suddenly my dolphin file manager started giving a strange problem. When I open a folder in super-user mode (with right click menu), I can not open any text files with kate/kwrite or anything for that matter. It says "kdeinit could not launch /usr/bin/kate".

I can 'su' in a terminal, and open the file with kate from terminal itself.

When I 'su' in aterminal and try to start dolphin by typing 'dolphin', it gives the following error message.

<unknown program name>(6612)/: KUniqueApplication: Cannot find the D-Bus session server:  "Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken."

<unknown program name>(6611)/: KUniqueApplication: Pipe closed unexpectedly.
Please help.