Windows will detect "Device Installation" and assign a drive letter. Your "Alcor Micro Unknown" should now be a functioning USB drive with full capacity.
Before attempting firmware updates, perform a hardware reset, as the controller might just be in a suspended state. Unplug the Alcor Micro device. the computer completely. Unplug the power cord (or remove the battery, if possible). Wait at least 2 minutes. Plug everything back in and boot up. Method 2: Driver Reinstallation
: This identifies the manufacturer of the USB controller chip . Alcor Micro (also known as 安国) is a Taiwanese fabless semiconductor company that designs, among other things, the controller chips that manage data flow on many USB flash drives.