In everyday use U disk, we will often happen: U disk plugged in computer use, according to the normal operation of the lower right corner click on the task bar "Unplug or Eject Hardware", and then select the desired pop-up U disk, and "USB Mass Storage device device can now be safely unloaded from the system" dialog box does not appear, but a "now can not stop generic volume device, stop the device again later." And after checking, U disk file is not no use for data transmission between the computer and the U disk. Why then is there this kind of situation?
After much research, preliminary guess when you insert U disk, will add a corresponding process in Task Manager, the corresponding process ends automatically when the normal pull out the hardware, the process does not end when the normal hardware will not be able to pull normal Out. To test this conjecture, we first open the Task Manager, go to "process" column, note that the lower left corner of the display are: "number of processes: 23", then insert U disk, and then to refocus on the "number of processes" However, when the system finds the hardware, everything is normal, the number of processes and not as I imagined changed to 24, but 23 remain unchanged. It would appear that when the U disk inserted and not the number of processes Correspondingly, this phenomenon is not explained.
While we have no choice but to click on the tray icon, when you want to uninstall U disk, suddenly found when clicking the "Stop USB Drive" process into a number of 24, that is to offload hardware "responsible" by one process, when hardware offload later, the process also ends. After several tests and found that the name of this process is rundll32.exe
Thus, we can conclude: when U disk can not be uninstalled normally, there is no progress bar must end rundll32.exe (Of course, some might rundll32.exe program and the system is running about), put a few rundll32.exe process ends, U disk can certainly normal uninstall.
Tips: If you often have this phenomenon can not stop the device, you can create a batch file, which enter "taskkill / im rundll32.exe", save as delusb.bat, run the event of failure about it. This method is more convenient.