simulink toolbox portability

I have a toolbox for simulink that used to work fine with version 7.0.1 now I have 7.9.0 and it does not work anymore. On running the model it gives the following message "Invalid MEX-file 'I:\Matlab\ESP\NST_DENS.dll': The specified procedure could not be found." I have the above said file in the folder but it seems I need to develop it again?? How do I go about fixing this.

Answer 1

[Walter Roberson]

Did you switch from using 32 bit before to using 64 bit now? If so then the old dll would not work.

[r2b]

Walter

I am using 32 bit and have not changed, the toolbox was made by some other person though and I am not sure what he used.

If I need to make a new dll file how should I go about it.

Answer 2

[Seth Popinchalk]

When MATLAB reports an Invalid MEX-file it usually means the file was compiled for a different platform (Win32 vs Win64) than the one you are running on. You recompile the file if you have the original source code.

Often for a file mymexfile.dll the source file is mymexfile.c.

To recompile it may be as simple as running the following command in the directory with the source file:

 mex mymexfile.c

If the MEX file has additional dependencies your compile command will be more complicated. See the following technical note about MEX

[Kaustubha Govind]

Also, you can determine whether your DLL is 32-bit or 64-bit by using dumpin (http://support.microsoft.com/kb/177429) with the /headers option.