Screen black after 90 degree re-orientation

[Loewi65]

I am lost :-(
I changed the system settings for my display, it went black after applying and does not come back.

I changed the display to 90 degree in order to read an electronical newspaper. Immediately after applying thy changes the display went black. I am a new with KUBUNTU.
My system is kubuntu 14.04 and my netbook is an ACER one D270
How can I change again the display again to the default settings when the display goes black when I boot?
I am able to log in as a guest user. Can I change the settings from there?

KDELibs-Version 4.13.3
Qt-Version 4.8.6
Kernel 3.13.0-53-generic
32 bit

I hope this makes sense and someone can help me :-)

[oshunluvr]

I can think of four or five ways to rotate a screen. You might enlighten us with the actual steps you took that resulted in your current situation.

[Loewi65]

I changed the settings for the display orientation. When I applied the change the screen went black.
I rebooted the system an when the symbol for settings appears during the boot process (screw driver and tool) the display goees black.
When I press Alt+Ctrl+F3 the terminal opens and I can enter name and password. Entering Alt+F7 freezes the screen and a mouse arrow appears. I can move the arrow which also changes at some point in the screen into grap mode. But I can see nothing except the frozen screen of the terminal.

[Loewi65]

Can I change the settings through the terminal commands?

[oshunluvr]

Ok, so you changed it in System Settings > Monitors? At least we know it's a user setting. Hopefully, someone will come along who knows where that setting is stored so you can delete or reset that file.

To change rotation in the terminal, the command is: xrandr --output <YOUR-OUTPUT-HERE> --rotate normal

To determine which output you're using, type xrandr and see which one is listed as connected. The rotate options are normal, left, inverted, and right

[SteveRiley]

Ok, so you changed it in System Settings > Monitors? At least we know it's a user setting. Hopefully, someone will come along who knows where that setting is stored so you can delete or reset that file.

Try deleting all the files in ~/.local/share/kscreen/. Do this when you're logged out of KDE and logged into a TTY console.

[Loewi65]

@Steve
I received also support from Daniel Vratil, the guy mentioned on the monitor settings page itself as a supporter.
He wrote
1) Logout
2) Switch to VT2 (Ctrl+Alt+F2) (or Ctrl+Alt+F{3,4,5....} if others don't work)
3) login to VT
4) rm ~/.kde/share/apps/kscreen/* (if ~/.kde does not exist, try ~/.kde4)
5) logout from VT
6) switch back to X (Ctrl+Alt+F7, but could be F1 as well)
7) login to KDE

This seems basically the same way which you suggested.
Now all is fine and works well again.
Thanks a lot!

[SteveRiley]

Yep, same suggestion. Glad it worked for you.