Here is my guide on how to install 2.3 generic and then root your x10.
First I would suggest installing the generic version of 2.3.
So, download the Flashtool - http://azuzu.spice.net.au/tools/X10_GB_Root/FlashTool_0.2.9.1-GBready_root_xRec.exe
Install it, then go to download the generic version of 2.3:
[Download] All X10 Firmwares - xda-developers
I downloaded X10a_3.0.1.G.0.75_AMERICA-US GENERIC 1233-8200.zip (140.5 MB)
Unzip the file and there should be a FTF file inside, that is the generic ROM
Open Flashtool, Click Flash, navigate to the FTF file that you unzipped.
Chose it, it will prepare the FTF file and then open a window asking you to turn your phone on in Flashmode.
Turn off phone and then hold the back button and plug in the USB cable at the same time like the window is asking you to do.
It will flash the phone to generic 2.3. Now we can prep it for rooting.
Turn the phone on, it will want you to go through the Wizard steps the first time. Just chose English and then click Skip (don't set it all up now)
Open Settings->Applications->Check Unknown Sources->click into Development->Check Debugging and check Stay Awake (for now, we need to do this)
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Phone is now 2.3 and ready to get rooted. We have to flash part of the kernel, root and then reflash back to the current kernel.
So, back in the flashtool, click Flash, there will be 2 files in the Firmware folder that is part of the flashtool. Chose the Kernel Downgrade and click ok, it will prep the files and get you ready to flash.
Turn off phone, hold the back button and plug in the USB cable like the onscreen instructions say and it will flsh to the downgraded kernel.
When it is done, unplug and turn off the phone.
Now, we need to root, the phone won't start so remove the back on the phone, we will need to pop the battery at some point.
Make sure the phone is off, have the flashtool open, and plug in the phone, and turn it on.
Click the Root button as soon as it lets you. If the root button never lights up, try once more (might have to pop the battery out to start again)
If you still can't click the root button in the flashtool, then when the phone starts, go to Advanced at the top of the menu bar in the x10 Flashtool and select Root and beside that select Force psneuter
In the flashtool, where it says what it is trying to do.
It used to say "Android version : 2.3.3 / kernel version : uname: permission denied" Now it says "Android version : 2.3.3 / kernel version : 2.6.29" or some other newer version. As long as it sys something like that, then it rooted.
Now we are ready to put the 2.3 kernel back on there and we are done.
Turn off phone (remove battery) now we start it in flashmode again. In the flashtool, click Flash and chose the Kernel Upgrade file from that firmware folder.
Plug in USB, hold back button and pop the battery back in, it will say it is flashing and ask you to unplug and reboot the phone when it is done.
That is it, it should be at 2.3 now and it should be rooted.
At this point, I would also do a Factory Reset on the phone, just to make sure anything left over from 2.1 is gone.
First I would suggest installing the generic version of 2.3.
So, download the Flashtool - http://azuzu.spice.net.au/tools/X10_GB_Root/FlashTool_0.2.9.1-GBready_root_xRec.exe
Install it, then go to download the generic version of 2.3:
[Download] All X10 Firmwares - xda-developers
I downloaded X10a_3.0.1.G.0.75_AMERICA-US GENERIC 1233-8200.zip (140.5 MB)
Unzip the file and there should be a FTF file inside, that is the generic ROM
Open Flashtool, Click Flash, navigate to the FTF file that you unzipped.
Chose it, it will prepare the FTF file and then open a window asking you to turn your phone on in Flashmode.
Turn off phone and then hold the back button and plug in the USB cable at the same time like the window is asking you to do.
It will flash the phone to generic 2.3. Now we can prep it for rooting.
Turn the phone on, it will want you to go through the Wizard steps the first time. Just chose English and then click Skip (don't set it all up now)
Open Settings->Applications->Check Unknown Sources->click into Development->Check Debugging and check Stay Awake (for now, we need to do this)
----------
Phone is now 2.3 and ready to get rooted. We have to flash part of the kernel, root and then reflash back to the current kernel.
So, back in the flashtool, click Flash, there will be 2 files in the Firmware folder that is part of the flashtool. Chose the Kernel Downgrade and click ok, it will prep the files and get you ready to flash.
Turn off phone, hold the back button and plug in the USB cable like the onscreen instructions say and it will flsh to the downgraded kernel.
When it is done, unplug and turn off the phone.
Now, we need to root, the phone won't start so remove the back on the phone, we will need to pop the battery at some point.
Make sure the phone is off, have the flashtool open, and plug in the phone, and turn it on.
Click the Root button as soon as it lets you. If the root button never lights up, try once more (might have to pop the battery out to start again)
If you still can't click the root button in the flashtool, then when the phone starts, go to Advanced at the top of the menu bar in the x10 Flashtool and select Root and beside that select Force psneuter
In the flashtool, where it says what it is trying to do.
It used to say "Android version : 2.3.3 / kernel version : uname: permission denied" Now it says "Android version : 2.3.3 / kernel version : 2.6.29" or some other newer version. As long as it sys something like that, then it rooted.
Now we are ready to put the 2.3 kernel back on there and we are done.
Turn off phone (remove battery) now we start it in flashmode again. In the flashtool, click Flash and chose the Kernel Upgrade file from that firmware folder.
Plug in USB, hold back button and pop the battery back in, it will say it is flashing and ask you to unplug and reboot the phone when it is done.
That is it, it should be at 2.3 now and it should be rooted.
At this point, I would also do a Factory Reset on the phone, just to make sure anything left over from 2.1 is gone.