I tried another time and the problem still there.. When in SP Flash Tool, I select scatter file, click 'Download' and connect the phone to PC, the process doesn't progress further. So, I have to finally click 'Stop' to quit. In the logs, it shows--
/****************************************************************/
\QT_FlashTool_Refactor\Conn\Connection.cpp,70)
09/14/2014 14:05:19.223 FlashTool[6724][1776][D]: APCore::ConnMediaUSB:

reConnect(): Scanning USB port...(..\QT_FlashTool_Refactor\Conn\ConnMedia.cpp,53)
09/14/2014 14:05:25.347 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:05:30.370 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:05:49.292 FlashTool[6724][1776][D]: USBSetting::SearchUSBPortPool(): Scaning USB port failed!(..\QT_FlashTool_Refactor\Conn\USBSetting.cpp,195)
09/14/2014 14:05:59.571 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:05:59.587 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:06:00.268 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:06:05.302 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:06:19.389 FlashTool[6724][1776][D]: USBSetting::SearchUSBPortPool(): Scaning USB port failed!(..\QT_FlashTool_Refactor\Conn\USBSetting.cpp,195)
09/14/2014 14:06:34.739 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:06:34.744 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:06:35.447 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:06:38.582 FlashTool[6724][6848][D]: MainController::StopByUser(): emit stop signal to background thread.(..\QT_FlashTool_Refactor\UI\src\MainController.cpp,265)
09/14/2014 14:06:38.582 FlashTool[6724][6848][D]: BackgroundWorker:

lot_stop_executing(): stopping,(0x03ED0E80,9876)(..\QT_FlashTool_Refactor\UI\src\BackgroundWorker.cpp,145)
09/14/2014 14:06:38.582 FlashTool[6724][6848][D]: MainController::StopByUser(): wait for thread finishing...(..\QT_FlashTool_Refactor\UI\src\MainController.cpp,268)
09/14/2014 14:06:38.612 FlashTool[6724][1776][D]: USBSetting::SearchUSBPortPool(): Scaning USB port failed!(..\QT_FlashTool_Refactor\Conn\USBSetting.cpp,195)
09/14/2014 14:06:38.612 FlashTool[6724][1776][D]: USBSetting::Search(): User stopped scanning USB port.(..\QT_FlashTool_Refactor\Conn\USBSetting.cpp,134)
09/14/2014 14:06:38.652 FlashTool[6724][1776][D]: BackgroundWorker::run(): User stopped.(..\QT_FlashTool_Refactor\UI\src\BackgroundWorker.cpp,82)
09/14/2014 14:06:38.652 FlashTool[6724][6848][D]: MainController::CreateNewThread(): creating a new working thread.(..\QT_FlashTool_Refactor\UI\src\MainController.cpp,293)
09/14/2014 14:06:38.652 FlashTool[6724][6848][D]: BackgroundWorker::BackgroundWorker(): ctor of BackgroundWorker...(..\QT_FlashTool_Refactor\UI\src\BackgroundWorker.cpp,17)
09/14/2014 14:06:38.653 FlashTool[6724][6848][D]: BackgroundWorker::~BackgroundWorker(): dtor of BackgroundWorker...(..\QT_FlashTool_Refactor\UI\src\BackgroundWorker.cpp,22)
09/14/2014 14:06:40.472 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:06:41.364 FlashTool[6724][6848][D]: ISetting:

et_stop_flag(): dummpy stop_flag(0x042513A8) set.(e:\qt flashtool\qt_flashtool_refactor\setting\ISetting.h,37)
09/14/2014 14:06:41.365 FlashTool[6724][5884][D]: APCore::MemoryTestSetting::CreateCommand(): memtest stop flag,(0x00000000)(..\QT_FlashTool_Refactor\Setting\MemoryTestSetting.cpp,49)
09/14/2014 14:06:41.365 FlashTool[6724][5884][D]: APCore::Connection::ConnectBROM(): Connecting to BROM...(..\QT_FlashTool_Refactor\Conn\Connection.cpp,70)
09/14/2014 14:06:41.365 FlashTool[6724][5884][D]: APCore::ConnMediaUSB:

reConnect(): Scanning USB port...(..\QT_FlashTool_Refactor\Conn\ConnMedia.cpp,53)
09/14/2014 14:07:09.911 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:07:09.917 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:07:10.616 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:07:11.421 FlashTool[6724][5884][D]: USBSetting::SearchUSBPortPool(): Scaning USB port failed!(..\QT_FlashTool_Refactor\Conn\USBSetting.cpp,195)
09/14/2014 14:07:15.600 FlashTool[6724][6848][D]: MainController::StopByUser(): emit stop signal to background thread.(..\QT_FlashTool_Refactor\UI\src\MainController.cpp,265)
09/14/2014 14:07:15.601 FlashTool[6724][6848][D]: BackgroundWorker:

lot_stop_executing(): stopping,(0x042513A8,9876)(..\QT_FlashTool_Refactor\UI\src\BackgroundWorker.cpp,145)
09/14/2014 14:07:15.601 FlashTool[6724][6848][D]: MainController::StopByUser(): wait for thread finishing...(..\QT_FlashTool_Refactor\UI\src\MainController.cpp,268)
09/14/2014 14:07:15.628 FlashTool[6724][5884][D]: USBSetting::SearchUSBPortPool(): Scaning USB port failed!(..\QT_FlashTool_Refactor\Conn\USBSetting.cpp,195)
09/14/2014 14:07:15.628 FlashTool[6724][5884][D]: USBSetting::Search(): User stopped scanning USB port.(..\QT_FlashTool_Refactor\Conn\USBSetting.cpp,134)
09/14/2014 14:07:15.628 FlashTool[6724][5884][D]: BackgroundWorker::run(): User stopped.(..\QT_FlashTool_Refactor\UI\src\BackgroundWorker.cpp,82)
09/14/2014 14:07:15.629 FlashTool[6724][6848][D]: MainController::CreateNewThread(): creating a new working thread.(..\QT_FlashTool_Refactor\UI\src\MainController.cpp,293)
09/14/2014 14:07:15.629 FlashTool[6724][6848][D]: BackgroundWorker::BackgroundWorker(): ctor of BackgroundWorker...(..\QT_FlashTool_Refactor\UI\src\BackgroundWorker.cpp,17)
09/14/2014 14:07:15.630 FlashTool[6724][6848][D]: BackgroundWorker::~BackgroundWorker(): dtor of BackgroundWorker...(..\QT_FlashTool_Refactor\UI\src\BackgroundWorker.cpp,22)
09/14/2014 14:07:15.646 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
09/14/2014 14:07:22.657 FlashTool[6724][6848][D]: ISetting:

et_stop_flag(): dummpy stop_flag(0x04254AA8) set.(e:\qt flashtool\qt_flashtool_refactor\setting\ISetting.h,37)
09/14/2014 14:07:22.658 FlashTool[6724][6776][D]: APCore::MemoryTestSetting::CreateCommand(): memtest stop flag,(0x00000000)(..\QT_FlashTool_Refactor\Setting\MemoryTestSetting.cpp,49)
09/14/2014 14:07:22.658 FlashTool[6724][6776][D]: APCore::Connection::ConnectBROM(): Connecting to BROM...(..\QT_FlashTool_Refactor\Conn\Connection.cpp,70)
09/14/2014 14:07:22.658 FlashTool[6724][6776][D]: APCore::ConnMediaUSB:

reConnect(): Scanning USB port...(..\QT_FlashTool_Refactor\Conn\ConnMedia.cpp,53)
09/14/2014 14:07:45.087 FlashTool[6724][6848][D]: OptionDialog::InitUARTInfo(): No com port detected.(..\QT_FlashTool_Refactor\UI\src\OptionDialog.cpp,416)
/*******************************************************/
Please advice how to resolve the issue.. I am totally stuck now. Thanks.