Hi,
I am getting started with OpenModelica. I have installed the last version but since three days (!!!), I am not able to run the simplest examples in the reference book ( Peter Fritzson, Principles of Object-Oriented Modeling and Simulation with Modelica). In particaul, the following commands:

class HelloWorld
   real x(start=1);
parameter Real a = 1;
equation
   der(x)=-a*x;
end HelloWorld;
simulate(HelloWorld, stopTime = 2)
plot (x)

I always get this error:
Error occured building AST
Syntax Error
[<interactive>:7:1-7:8:writable] Error: Parser error: Unexpected token near: simulate (IDENT)

Please, does some body have an idea. I can't run neither examples in the Users' guide.

I am a former user of VBA and Matlab.

Windows 7
OpenModelica 1.8.0