INVALID_FUNCTION error when writing to HID file - c++

Question

I am writing a program to send data to an HID device. I followed the following page from Microsoft's documentation: Finding and Opening a HID Collection and I get the file handle successfully, but when I try to write using WriteFile, I get an INVALID_FUNCTION error (1). I have sent the same data to the device through a Hyperterminal and it worked, so I'm sure that the information I am sending is correct.
Here is my code:
HANDLE m_hCommPort;
GUID guid = GUID_DEVINTERFACE_USB_DEVICE;
HDEVINFO hinfo;
DWORD index = 0;
SP_DEVICE_INTERFACE_DATA deviceInterfaceData;
SP_DEVINFO_DATA deviceInfoData;
BOOL result;
PSP_DEVICE_INTERFACE_DETAIL_DATA deviceInterfaceDetailData = NULL;
DWORD requiredSize;
DWORD deviceIndex = 0;
hinfo = SetupDiGetClassDevs(&guid, NULL, NULL, DIGCF_DEVICEINTERFACE | DIGCF_PRESENT);
deviceInterfaceData.cbSize = sizeof(SP_DEVICE_INTERFACE_DATA);
result = SetupDiEnumDeviceInterfaces(hinfo, NULL, &guid, deviceIndex, &deviceInterfaceData);
while (result == TRUE) {
deviceInfoData.cbSize = sizeof(deviceInfoData);
SetupDiGetDeviceInterfaceDetail(hinfo, &deviceInterfaceData, NULL, 0, &requiredSize, &deviceInfoData);
deviceInterfaceDetailData = (PSP_DEVICE_INTERFACE_DETAIL_DATA)malloc(requiredSize);
deviceInterfaceDetailData->cbSize = sizeof(SP_DEVICE_INTERFACE_DETAIL_DATA);
SetupDiGetDeviceInterfaceDetail(hinfo, &deviceInterfaceData, deviceInterfaceDetailData, requiredSize, NULL, &deviceInfoData);
Trace(TEXT(deviceInterfaceDetailData->DevicePath));
if (_tcsstr(deviceInterfaceDetailData->DevicePath, "vid_0c2e&pid_0be7")) {
Trace(TEXT(deviceInterfaceDetailData->DevicePath));
break;
}
result = SetupDiEnumDeviceInterfaces(hinfo, NULL, &guid, ++deviceIndex, &deviceInterfaceData);
}
if (result == FALSE) {
ErrorExit("SetupDiEnumDeviceInterfaces ");
}
else if(deviceInterfaceDetailData != NULL){
m_hCommPort = CreateFile(deviceInterfaceDetailData->DevicePath, GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, 0);
if (m_hCommPort == INVALID_HANDLE_VALUE) {
ErrorExit("CreateFile");
}
else {
DWORD bytesWritten;
char scanCommand[] = { 22,77,13,'I','M','G','S','N','P','1','B' };
DWORD size = sizeof(scanCommand);
BOOL fileWritten = WriteFile(m_hCommPort, scanCommand, size, &bytesWritten, NULL);
if (fileWritten == TRUE) {
Trace(TEXT("Wrote %d files to device"), bytesWritten);
}
else {
ErrorExit("Error writing to file");
}
}
}
Can someone help me to understand why I am getting this error please?