Simulink compability r2011b vs r2012b

I have a slx. (Simulink) file that have a embedded stateflow block. The model was built and run in a Matlab r2011b version. Now I´m trying to run the model in a Matlab r2012b and the following error appears.

ERROR:

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Making simulation target "PCM_Sala2_sfun", ...

C:\Users\ricardo.pereira\Documents\MATLAB\Modelo_PCM_Professor_Joyce\slprj\_sfprj\PCM_Sala2\_self\sfun\src>call "mexopts.bat"

Microsoft (R) Program Maintenance Utility Version 10.00.30319.01

Copyright (C) Microsoft Corporation. All rights reserved. ~

### Compiling "PCM_Sala2_sfun.c"

cl.exe /c /Zp8 /GR /W3 /EHs /D_CRT_SECURE_NO_DEPRECATE /D_SCL_SECURE_NO_DEPRECATE /D_SECURE_SCL=0 /DMATLAB_MEX_FILE /nologo /MD /c /GR /W3 /EHs /D_CRT_SECURE_NO_DEPRECATE /D_SCL_SECURE_NO_DEPRECATE /D_SECURE_SCL=0 /DMATLAB_MEX_FILE /nologo /MD /I "C:\Program Files\MATLAB\R2012b\extern\include" /I "C:\Program Files\MATLAB\R2012b\simulink\include" /I "C:\Program Files\MATLAB\R2012b\stateflow\c\mex\include" /I "C:\Program Files\MATLAB\R2012b\stateflow\c\debugger\include" "PCM_Sala2_sfun.c"

PCM_Sala2_sfun.c

C:\Program Files\MATLAB\R2012b\stateflow\c\mex\include\sfc_sf.h(33) : fatal error C1083: Cannot open include file: 'mwmathutil.h': No such file or directory

NMAKE : fatal error U1077: '"C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\bin\amd64\cl.exe"' : return code '0x2'

Stop.

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I have the windows SDK 7.1 installed and it runs well with commands like "ssd_build".

I look for all internet. I dont found the mwmathutil.h file in internet.

Can anyone help me with this error?

[Kaustubha Govind]

mwmathutil.h should be present in C:\Program Files\MATLAB\R2012b\simulink\include - do you see it there?