How to open an old version MDL file?

how I can use an old version program of an MDL file in Simulink?

The file that I need to use is Version 2.09. Someone know how i can used it?

[Walter Roberson]

I am having difficulty tracking that version back to the corresponding MATLAB release?

A bound is that MATLAB 5.3 has Simulink 3.0 already.

Answer 1

[Sulaymon Eshkabilov]

Most of the cases, MATLAB/Simulink is backward compatible, in other words, the models created in older versions should be opened in newer versions without any problem. See this DOC how to manage model versions.