Dynamically loaded DLL access violation

Apologies in advance if this isn’t the correct group.

I’m trying to dynamically load a third party DLL and call one of
its functions but I keep getting an access violation.  At first I
thought the problem was in the DLL but if I change the code to
statically load the DLL it works fine.  Can anyone help?  I’ve
posted both version of the code below for reference (Delphi 6).

The function takes 2 parameters, an integer error code and a
string.  The idea being you pass in the error code and it returns
the error description.


//
// Dynamic code – causes an access violation
//

procedure TForm1.Button1Click(Sender: TObject);
type
   TGetErrorText = function(iErrorCode: Integer; pErrorText: PChar): Integer;
var
   hDLL: THandle;
   fFunc: TGetErrorText;
   aText: array[0..256] of Char;
begin
   hDLL := LoadLibrary('C:\max32.dll');
   if hDLL <= HINSTANCE_ERROR then
      raise Exception.Create('Unable to load the library.');

   @fFunc := GetProcAddress(hDLL, 'GetErrorText');
   if @fFunc <> nil then
   begin
      fFunc(19, @aText);
      Label1.Caption := aText;
   end;

   FreeLibrary(hDLL);
end;

//
// Static code – works fine
//

function GetErrorText(iErrorCode: Integer; pErrorText: PChar): Integer; stdcall; external 'C:\max32.dll';

procedure TForm1.Button1Click(Sender: TObject);
var
   aText: array[0..256] of Char;
begin
   GetErrorText(19, @aText);
   Label1.Caption := aText;
end;


TIA
Stephen