SP not booting after attempting to install Cyanogenmod

[starshine]

I have tried to install Cyanogenmod (latest nightly) by following these instructions. I had some difficulties to get fastboot and adb working on my Ubuntu pc, but after all everything seemed to work fine. I installed Cyanogenmod using the sideload method, and added a package containing Google apps. Then I returned to the main menu and selected reboot system now, but now all that happens is the text "SONY" to appear in white font at a black background. After some seconds it disappears, and after some more time this process repeats. I can't seem to turn the phone off, which is required to boot it in fastboot mode (power down, volume up, insert usb cable). Please help...

[Thommo]

To fully switch off your phone hold volume up and power for around 10 to 15 seconds or untill you feel 3 quick vibrations

[starshine]

This doesn't help. No matter how long I keep volume up and power pressed, it never switches off and I never feel the phone vibrate.

If I connect the USB-cable and press volume up and power simultatiously for some time I get the CWM (ClockworkMod Recovery?) utility, but it doesn't help to solve my issue. Restoring a backup from my SD-card or whatever I try it doesn't work. And it doesn't have a feature to put my phone in fastboot mode.

[Thommo · Accepted solution]

If you unlocked your bootloader then you will only be able to get back to stock via a manual flash using flashtools and a .ftf firmware file - You can also turn your phone off by removing the back cover and at the bottom you will see OFF and using the tip of an object like a pin etc you can press this - Then as I'm sure you know holding volume up and connecting a usb cable enters fastboot and volume down and connecting your cable enters flashmode which is what you need to use flashtools

[starshine]

Thx Tommo. I managed to switch off my phone by pressing the OFF "button" below the back cover, and than I found out about Sony's "Emma" Flash tool, and was able to restore the original ROM to my phone (even though it is not on the supported phones list). So no Cyanogenmod, but at least I have a working phone again.

[frantizsekk]

I have put in  cyanogen 11 *The Duxton*  You do not need unlocked bootloader for this version, it works perfectly