HI, There is a solution for Pendrive not detecting or usb drive not visible in My computer and device manager. Recently I had a problem with Sandisk Cruzer Micro 4 gb pendrive. When I inserted the pen drive the system is detecting but it is not visible in Windoes explorer and device manager. But it is working in other computers. So it is not damaged or virus infected. If you Open Disk management there you will find your pendrive without any drive letter. Here the problem is not with the pendrive, it is with the system. To resolve this I tried in many ways and installed driver detecting softwares, but there is no use. Finally I succeeded in the following method. The problem occured because unexpectedly the drive was un-mounted. 1) To solve you should have Administrator privilages on your local system. 2) Later go to Local security policy select Local policies in that select Audit policy and select Audit object access and check Success and apply. 3) From RUN, type diskpart and right click on it and select Run as Administrator 4) At the DISKPART prompt, type automount press enter next type recover press enter next type rescan press enter and exit 5) In Device manager under storage devices find your device not recognized and uninstall it. 6) Unplug the device and plug it again then the driver automatically installs and it is mounted to your computer. You will get the autoplay window. Thats it.