I cannot open the configuration, System Setting > Application Appearance in icon view.While I was changing Style, the window was closed and I cannot open it again. System Setting window is closed immediately when I click Application Appearance icon in icon view or when I click Style in classic tree view. I believe this is a kind of bug in System Setting.

It happened before, at that time I removed ~/.kde4 folder. And KDE automatically made all configuration to default. It was not easy to recover back to how it was configured. I do not think that way a good. I do not want to do that again.

Anyone know how do I set up only Style configuration to default?

Dr Konqi should open automatically when System Settings crashes. Try running "kcmshell4 style" via gdb if it doesn't to try and debug this.

When I run "kcmshell4 style" from terminal emulator, it opens and close immediately with nothing.

I guess there must be a configuration file under ~/.kde4. Isn't there?

I ran "grep gtk *" under ~/.kde4/share/config/". I found the file name. And I deleted a line from the file. That like contained the style name. It was gtk+. After that, every thing works fine. Thank you for helps.