Kubuntu 14.04 X console immediately logged out problem

When I tried to login from X console, I was immediately logged out and cannot login.

1. first try to login by tty. (Control-Alt-F1, for example) I can login by the tty.

2. Check the ~/.xsession-errors file. I have the following (or similar) message.

/etc/X11/Xsession.d/99x11-common_start ...

Open the /etc/X11/Xsession.d/99x11-common_start file. The line that has an error is

exec $STARTUP

Some reason, $STARTUP seems not correct.

3. Solution: I commented out that line with #, like,

# exec $STARTUP

Then it worked again. But, I am not sure what is really causing.

Comments

Why A^{T}A is invertible? (2) Linear Algebra

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Here is my question. The area of parallelogram is the difference of these two rectangles (red rectangle - blue rectangle). This is not intuitive for me. If you also think it is not so intuitive, you might interested in my slides. I try to explain this for hight school students. Slides: A bit intuitive (for me) explanation of area of parallelogram (to my site, external link) .

Lx=d: SundayResearch

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