Bat file stopping and i'm not sure why - batch-file

Question

So, I have a bat file I've been building to do a simple profile backup/restore. I'm running Windows 7 64bit.
I get through 99% of the script until it gets to this point and then dies. To be clear, in the environment I'm working in, I HAVE to turn off UAC for certain things. Someone much higher up than me made that call.
However, this needs to do this but it dies after the "[ COMPLETE ]" is echoed. It doesn't close the window, it just goes back to the C prompt.
The only other thing it's going (trying) to do after that is log the user off after a 15 second timer.
Any help would be much appreciated.
echo [ Turning off UAC... ]
C:\Windows\System32\cmd.exe /k %windir%\System32\reg.exe ADD HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System /v EnableLUA /t REG_DWORD /d 0 /f
ping -n 2 -w 1000 127.0.0.1 > nul
echo [ COMPLETE ]
ping -n 2 -w 1000 127.0.0.1 > nul
echo.
ECHO ==========================================================
ECHO = Restore Complete =
ECHO = Computer will logoff in 15 seconds to apply changes. =
ECHO ==========================================================
TIMEOUT 16
shutdown /l
#pause
:EOF

Answer 1

I made a test batch file that does what you're trying:
#echo off
echo before
cmd /k echo I'm doing it!
echo after
And here was the result:
C:\files\j>test
before
I'm doing it!
So I changed it to call:
#echo off
echo before
call echo I'm doing it!
echo after
And got this:
C:\files\j>test
before
I'm doing it!
after
So clearly, /k isn't for you. But CALL will put it in a new shell... So my recommendation is to just change that line to be :
%windir%\System32\reg.exe ADD HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System /v EnableLUA /t REG_DWORD /d 0 /f
No cmd, no \k, no anything - just run the REG.exe.
If you have to, use the CALL since you're adding a registry key and it should stay there.