libusb_bulk_transfer() only works once - c++

Question

I'm completely new to Libusb. I have written a c++ program in Ubuntu, I can connect to the device, I transfer some data to the device using libusb_bulk_transfer(...). It works the first time, but the second time it returns -1 code. But when I reject the device and then when I reinstall the device to my computer, it works again.
Here is my code:
#include <iostream>
#include <stdio.h>
#include <libusb.h>
using namespace std;
#define BULK_OUTPUT LIBUSB_ENDPOINT_OUT | 0x01
#define BULK_INPUT LIBUSB_ENDPOINT_IN | 0x01
union usb_relator {
unsigned char usb_data[4];
int32_t number;
};
int main()
{
libusb_device_handle *handle = NULL;
if (libusb_init(NULL) < 0)
{
cout << "Failure" << endl;
return 0;
}
cout << "libusb inited successfully!!" << endl;
libusb_device **devices;
libusb_get_device_list(NULL, &devices);
if (libusb_open(devices[0], &handle) < 0)
{
cout << "The device can not be open!!" << endl;
return 0;
}
cout << "device opened successfully!!" << endl;
libusb_device_descriptor descriptor;
libusb_get_device_descriptor(devices[0], &descriptor);
cout << "Vendor id: " << (int)descriptor.idVendor << endl;
cout << "Product Id: " << (int)descriptor.idProduct << endl;
libusb_detach_kernel_driver(handle, 0);
if (libusb_claim_interface(handle, 0) < 0)
{
cout << "Can not claim interface!!" << endl;
return 0;
}
cout << "Handle has been claimed!!" << endl;
if (libusb_set_interface_alt_setting(handle, 0, 0) < 0)
{
cout << "Could not set alternate setting of the handle!!" << endl;
return 0;
}
cout << "alt_setting set successfully!!" << endl;
usb_relator number;
cout << "Please insert your number: ";
cin >> number.number;
int transfer_size;
int returnCode = libusb_bulk_transfer(handle, BULK_OUTPUT, number.usb_data, sizeof(usb_relator), &transfer_size, 5000);
if (returnCode == 0)
{
cout << "Data sent!!" << endl;
}
else
{
cout << "Data could not be send!! Code: " << returnCode << endl;
}
returnCode = libusb_bulk_transfer(handle, BULK_INPUT, number.usb_data, sizeof(usb_relator), &transfer_size, 5000);
if (returnCode == 0)
{
cout << "Data recieved!!" << endl;
cout << number.usb_data << endl;
}
else
{
cout << "Data could not recieve!! Code: " << returnCode << endl;
}
libusb_release_interface(handle, 0);
libusb_close(handle);
libusb_free_device_list(devices, 1);
libusb_exit(NULL);
}
I'm using Ubuntu 14.04, and I'm using VMWare. Thanks for your help.
I think it has something to do with the libusb_detach_kernal_driver(...) methode I call in my code.(Right before the line I claim the interface).