compiling error [Simmechanics I]

This message I get after sim('......mdl')and the file status keeps noticing "compiling" but never finish.

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Caught "std::exception" Exception message is:
The specified superclass 'PM_VIS.AnimFigVis' contains a parse error or cannot be found on MATLAB's search path, possibly shadowed by another file with the same name. 
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Any one know what is this error about.

Thanks a lot

PS: I am using matlab R2013b to run this simechanics program, made in Matlab2012a. For my guess, I don't think this is a version problem but for your information

[Hung Vu]

I would like to add more information. This issue occurs when I enable the animation during simulation. If the animation is turn off, no problem arises.