USB Mass Storage Driver
These 3 files should exist (or the driver is corrupt)
C:Windowsinfusbstor.inf
C:Windowsinfusbstor.pnf
C:Windowssystem32driversusbstor.sys
If one or more of these files are missing
Navigate to C:WindowsSystem32DriverStoreFileRepository
Scroll down. Find the folder name that starts with usbstor.inf_
You may see more then one folder with name starting usbstor.inf_. IF YOU DO: you want the folder with the most recent date
Open the folder. There's a copy of the 3 files you need. Copy each one to its correct location as shown above
Jump to the instructions below to delete the INFCACHE.1 file