[Sony Xperia Z Ultra] SUPERUSER:
mm I have not had much luck with vnc servers on android.

My phone force closes remotedroid..got the server working by lowering the resolution in settings but I get no data to my client.

Tried on another device and the app crashes as soon as I start the server. And it said my devie is rooted in the toast..its not.

And it give me a black screen when I connect as a client...oh..jesus. It says in the app "4. The serve app will ONLY work on a rooted KitKat device and the app must be installed in /system." ..not reading the instructions works really good.

Hang on..I found a vnc server that works! For lollipop.

http://www.apkmonk.com/app/com.pranayc.remotevncserver/

huh..this is the very first time I have got vnc working on android! :D

I get image but no controls..You can try RemoteDroid and report if it works in case you succeed to root your phone.

You can go the long way and compile a vnc server from source code and run it from terminal but its not the practical way when you can run teamviewer instead..

So next problem:

Its not possible to install the dialer apk?

https://www.apkmirror.com/apk/google-inc/google-dialer/

Its a long shot. But you can try..if it will even install.

There is this guide. But I cant make this work on marshmallow.

I don't have any devices running stock lollipop or older to test the old contacts app with.

http://www.xperiablog.net/2013/06/20/xperia-tablet-z-how-to-access-the-service-menu/

Long pressing in the contacts app does nothing in marshmallow.

I found this thread: https://xdaforums.com/showthread.php?t=2289383

adb shell "am start -a android.intent.action.MAIN -n com.sonyericsson.android.servicemenu/.ServiceMainMenu"

But I get the following: (again running marshmallow)

Starting: Intent { act=android.intent.action.MAIN cmp=com.sonyericsson.android.s
ervicemenu/.ServiceMainMenu }
Error type 3
Error: Activity class {com.sonyericsson.android.servicemenu/com.sonyericsson.and
roid.servicemenu.ServiceMainMenu} does not exist.

The issue OP was running into with flashtool won't affect you unless you're running the same Windows 10 pro version whatever build op was on and the same flashtool. I recommend running a separate windows 7 machine physical or virtual machine for messing with drivers and this stuff.

Quoting the op post

A. Roll back the firmware to one old enough for the root tool to work, root the tablet, and update the firmware back to the latest one.

B. Find the absolute kernel addresses and use 'iovyroot' to root (this should be able to root the device with the current firmware).

Neither of these are going to work. B...if you have freetime to spend go ahead but its eh. Go out and have fun this summer instead of staring on a hex editor.

Today ..I mean today in july 2017 we have some issues.

That is that its almost impossible to obtain older stock roms.

Xperiafirm removed all but the latest. Filehosts posted here has removed the file due to inactivity.

I found two stock roms for SGP412 to download in case you need it. I can't find it in flashtool.

Dunno if sol24 is the same device or if sol24 and SGP412 are two different models?

https://www.androidfilehost.com/?fid=24566382913913003

https://www.androidfilehost.com/?fid=24562946973630839

But get back to the dialer. My guess to why you want to access the service menu might be to check if bootloader unlocked allow will be yes or no?

And it being impossible to root the device perhaps this is what you want to do? And then root the phone with the bootloader unlocked?

I don't know the mechanisms applied by sony to stop it to being able to root. But hopefully it might be possible to overcome with unlocked bootloader.