[Sony Ericsson XPERIA X10 Mini] WhB/K:
Until now, i powered my phone (U20) with MiniCM7pro.

Yesterday i wanted to update the phone on MiniCM7-2.2.1 with nAa-11 but i'm not able to install the Kernel.

After two hours i switched back to stock kernel but the problem are still alive.

Now, my mobile runs on stock Kernel (flashed with seus), i rooted the phone with flashtool. Unknown Sources and Debugging are switched on.

When i try to install nAa-11 Flashtool (0.2.8) shows the following Error:

22/007/2012 08:07:33 - INFO - Searching Xperia....

22/007/2012 08:07:34 - INFO - Found at USB\VID_0FCE&PID_ADDE\5&21AF9BF0&0&1

22/007/2012 08:07:34 - INFO - Start Flashing

22/007/2012 08:07:34 - INFO - VER="R8A029";DATE="20100601";TIME="12:17:00";

22/007/2012 08:07:34 - INFO - Flashing loader

22/007/2012 08:07:34 - ERROR - Error flashing. Aborted

22/007/2012 08:07:34 - INFO - Now unplug the device and power it on

22/007/2012 08:07:34 - INFO - Then go to application settings

22/007/2012 08:07:34 - INFO - turn on Unknown Sources and Debugging

22/009/2012 08:09:11 - INFO - Connected device : U20

22/009/2012 08:09:11 - INFO - Installed version of busybox : BusyBox v1.15.3 (2010-02-06 17:13:19 CET) multi-call binary

22/009/2012 08:09:47 - INFO - Preparing files for flashing

22/009/2012 08:09:48 - INFO - Searching Xperia....

22/009/2012 08:09:48 - ERROR - Please plug you device in flash mode

22/009/2012 08:09:49 - INFO - Searching Xperia....

22/010/2012 08:10:24 - INFO - Found at USB\VID_0FCE&PID_ADDE\5&21AF9BF0&0&1

22/010/2012 08:10:24 - INFO - Start Flashing

22/010/2012 08:10:24 - INFO - VER="R8A029";DATE="20100601";TIME="12:17:00";

22/010/2012 08:10:24 - INFO - Flashing loader

22/010/2012 08:10:24 - ERROR - Error flashing. Aborted

22/010/2012 08:10:24 - INFO - Now unplug the device and power it on

22/010/2012 08:10:24 - INFO - Then go to application settings

22/010/2012 08:10:24 - INFO - turn on Unknown Sources and Debugging

Flashtool 0.8.0.0 the same problem:

22/059/2012 08:59:00 - INFO - <- This level is successfully initialized

22/059/2012 08:59:00 - INFO - Flashtool Version 0.8.0.0 built on 2012-05-27 21:57:12

22/059/2012 08:59:00 - INFO - You can drag and drop ftf files here to start flashing them

22/059/2012 08:59:05 - INFO - Device disconnected

22/059/2012 08:59:39 - INFO - Selected U20_nAa-11_2.6.29.6-nAa-11.ftf

22/059/2012 08:59:39 - INFO - Preparing files for flashing

22/059/2012 08:59:39 - INFO - Please connect your device into flashmode.

22/059/2012 08:59:47 - INFO - Device connected in flash mode

22/059/2012 08:59:47 - INFO - Opening device for R/W

22/059/2012 08:59:47 - INFO - Reading device information

22/059/2012 08:59:47 - INFO - Phone ready for flashmode operations.

22/059/2012 08:59:47 - INFO - Start Flashing

22/059/2012 08:59:47 - INFO - Flashing loader

22/059/2012 08:59:47 - INFO - Ending flash session

22/059/2012 08:59:47 - ERROR - ERR_SEVERITY="MAJOR";ERR_CLASS="SECURITY_CLASS";ERR_DYNAMIC="SIN header verification failed"

22/059/2012 08:59:47 - ERROR - Error flashing. Aborted

22/059/2012 08:59:48 - INFO - Device connected in flash mode

22/059/2012 08:59:49 - INFO - Device disconnected

22/059/2012 08:59:51 - INFO - Device connected in flash mode

22/000/2012 09:00:10 - INFO - Device disconnected

22/000/2012 09:00:14 - INFO - Device connected with USB debugging off

22/000/2012 09:00:14 - INFO - For 2011 devices line, be sure you are not in MTP mode

I'm at a loss. What is my mistake?