I am getting an error using calllib () operation....pls help

Connecting with Neurosky Mindwave Mobile

aaa='Acquiring EEG Signal';
set(handles,'String',aaa);
condition=0;
returncommand=0;

%preallocate buffer
data = zeros(1,256);   
%COM Port #
portnum1 = 9;   
comPortName1 = sprintf('\\\\.\\COM%d', portnum1);
%BaudRate Settings
TG_BAUD_57600 =      57600;
TG_STREAM_PACKETS =     0;
% TG_DATA_RAW =         4;
% Data type that can be requested from TG_GetValue().
TG_DATA_POOR_SIGNAL =     1;
TG_DATA_ATTENTION =       2;
TG_DATA_MEDITATION =      3;
TG_DATA_RAW =             4;
TG_DATA_DELTA =           5;
TG_DATA_THETA =           6;
TG_DATA_ALPHA1 =          7;
TG_DATA_ALPHA2 =          8;
TG_DATA_BETA1 =           9;
TG_DATA_BETA2 =          10;
TG_DATA_GAMMA1 =         11;
TG_DATA_GAMMA2 =         12;
TG_DATA_BLINK_STRENGTH = 37;
%Load ThinkGear.dll
loadlibrary ('ThinkGear.dll','thinkgear.h')
fprintf('ThinkGear.dll loaded\n');
%get dll version
dllVersion = calllib('ThinkGear', 'TG_GetDriverVersion');
fprintf('ThinkGear DLL version: %d\n', dllVersion );
%GET A CONNECTION ID HANDLE TO THINKGEAR
connectionId1 = calllib('ThinkGear', 'TG_GetNewConnectionId');
if ( connectionId1 < 0 )
  error( sprintf('ERROR: TG_GetNewConnectionId() returned %d.\n', connectionId1)) ;
end

Error Im getting....

Warning: The library class 'ThinkGear' already exists.  Use a classname alias.

ThinkGear.dll loaded

Error using calllib
Method was not found.