If I use OMEdit to create a new model by going:

File-->New Modelica Class-->'Insert Name' with default Specialisation set to Model-->OK

and create a model, say a DC motor, as in the tutorial video, and I save the model. Then I am unable to open the model again later.

When I try to open the model I get the error message:

---------
Error has occured while loading the file/library
Path to file
Unable to load the file/library

Redefining class(es) 'filename' which already exist(s). Delete the
existing class(es) before loading the file/library
Path  to file
---------

This error message seems like it must be very clear but I am completely new to Modelica and have no idea what it means.

I will be very greatful if any one can assist me.

Regards
Michael