Error with string as a constructor parameter?

[Robotics Guy]

Here's my code:

#include <string>

#ifndef MAIN_H

class MyClass
{
public:
	MyClass();
	MyClass(string myString);
};

MyClass::MyClass()
{
}

MyClass::MyClass(string myString)
{
}

#endif

Visual Studio gives me the following error:



If I change myString to type INT, there is no compilation error. So what am I doing wrong?