[fixed] can not open display :0?

Question

I don't know which part cause this error, I'm using KDE and intel's driver, everty time I boot the system, run an application, it will fail with "cannot open display". Then I need to log out and log in, then every thing will fine.
    And sometime the system will freeze when wake up from sleep state, lock screen's background is displayed but no password input dialog.
These issues is quite similar, but I just don't know where they are from. But at least this is a system issue, not a single application.
Last edited by ThomasKing0529 (2014-10-07 03:49:35)

Answer 1

Sorry to reply so late
Yeah, it's now definitely a problem, every time I start system, then every application won't open with this error. And just as I explained, they all tell me they can't open display or just with another message: "No protocol specified". The first time I see this error message is when I install VMware Player.
And now the details of this problem: it will appear after entering KDE desktop, and cause everything with GUI(Qt or Gtk) failed to run. This is not a problem raised immediately: Cause I can run Konsole at first, but then everything including Konsole will not run.
As root privilege cause this problem, and I use sudo to connect to network, maybe this is a bug of Konsole?
Seems not, cause I can get out of this by re-login, this must be a bug of KDE anyway. 
That's all I can supply. In fact, I'm really confused by this problem. And horribly, I'm being used to this problem, I'm being used to log out and log in to get out of this problem.
Maybe this is why I forgot to reply this post, sorry again for this.