The function called, via a function pointer, was declared with a prototype. 

However, the given parameter number (counting left to right from 1) could not be converted to the declared parameter type. 

When compiling C++ programs, this message is always preceded by another message that explains the exact reason for the type mismatch. 

That other message is usually "Cannot convert 'type1' to 'type2'" but the mismatch might be due to many other reasons.