Windows 7 does not detect USB mass storage devices anymore

Someone pointed me to a post in sevenforums.com by Difusal. After following the steps in the post, I deleted the entry with the exclamation mark in the Device Manager, then replugged the device. The mass storage driver installed automatically, and the drive is now detected.

Steps, copied from the aforementioned forum post, reformatted and with typos and spelling corrected:

1. Open Windows Explorer.

2. Go to C:\Windows\System32\DriverStore.

   You will have a couple of folders and files.

   You will have *.dat files and another file named: infcache.1

3. Right click every file (don't touch the folders!) and choose properties.

4. Go to the Security tab.

5. Click Edit.

6. Choose your account and check the box: Full Control (see ss)

7. Click OK.

8. Repeat for every file.

9. Select all the files (*.dat and infcache.1).

10. Press Shift + Del.

11. Click OK.

12. Now, go to C:\Windows\System32\Driver Store\File Repository.

13. Search folders containing usbstor.inf.

14. Open it (if you have more than one, choose the most recent).

15. Copy usbstor.inf and usbstor.PNF.

16. Paste those two files to C:\Windows\inf.

17. Reboot your PC and voilà! :b

Find the hardware ID of the device by right clicking on the device selecting properties and navigating to Details then hardware ids in the drop-down menu.

Take the top one and search it on Google preferably. See if you can find the corresponding device or if your lucky, the recommended driver for the device and download that from the support page of lenovo.