EZcheats.

bool spoof_volume_id(char drive)
{
	const int max_pbsi = 3;

	struct partial_boot_sector_info
	{
		LPCSTR Fs; // file system name
		DWORD FsOffs; // offset of file system name in the boot sector
		DWORD SerialOffs; // offset of the serialnumber in the boot sector
	};

	partial_boot_sector_info pbsi[max_pbsi] =
	{
	 {"FAT32", 0x52, 0x43},
	 {"FAT",   0x36, 0x27},
	 {"NTFS",  0x03, 0x48}
	};

	char buf[64];
	sprintf_s(buf, "\\\\.\\%c:", drive);

	HANDLE hFile = CreateFileA(buf, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, nullptr, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
	if (hFile == INVALID_HANDLE_VALUE)
		return false;
	BYTE sector[0x200];
	DWORD dwBytesRead;
	bool result = false;
	if (ReadFile(hFile, sector, sizeof(sector), &dwBytesRead, nullptr)) {
		int i;
		for (i = 0; i < max_pbsi; i++)
		{
			if (strncmp(pbsi[i].Fs, (const char*)(sector + pbsi[i].FsOffs), strlen(pbsi[i].Fs)) == 0)
			{
				// we found a valid signature
				break;
			}
		}

		if (i < max_pbsi) {
			printf("drive: %c, Serial: %X\r\n", drive, *(PDWORD)(sector + pbsi[i].SerialOffs));
			*(PDWORD)(sector + pbsi[i].SerialOffs) ^= generate_volume_serial_number();
			printf("drive: %c, Spoofed Serial: %X\r\n", drive, *(PDWORD)(sector + pbsi[i].SerialOffs));
			if (INVALID_SET_FILE_POINTER != SetFilePointer(hFile, NULL, NULL, FILE_BEGIN)) {
				DWORD dwBytesWritten;
				result = ::WriteFile(hFile, sector, sizeof(sector), &dwBytesWritten, nullptr) == TRUE;
			}
		}
		else
			printf("unknown fs\r\n");
	}

	::CloseHandle(hFile);
	return result;
}