Can you think of any device you used to have plugged into a USB port, but now no longer use?
If so, go into Device Manager and click the View tab and choose View Hidden Devices then uninstall any old devices that you no longer use.
Failing that, download and install the free version of CCleaner then run it to clean up the system registry.
http://www.piriform.com/CCLEANER
IMPORTANT: Please create a system restore point before you use CCleaner.
I have no old devices and pc registry is already clean, cache and other things too. The thing is that this error only happens for storage devices such as usb pen drives and other bigger external hard drives, while usb device like mouse and keyboard have no problems even when unplugging and plugging again.
In that case, I'm out of ideas.
With a bit of luck, someone else may have an answer.
Hi, natostanco.
You could try this Microsoft Fix it solution to see if it solves your problem: Hardware devices are not working or are not detected in Windows
i have problem with code 38 too, the way i solve it is: right click at my computer then click Properties then click device manager(at left bar) then, at lowest you'll see universal bus series then i uninstal: 1.Generic USB Hub and 2.USB Root Hub. then restart, after that computer will automatic install the missing driver, then your USB is work (code 38 gone!!)
-i dont know if it will success for you or not but atleast that what i do and i success, and last do at your own risk (i just try contribute to help) ^^
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