when you say "regardless of whatever kind of USB device" tht puzzles me.
I've seen this problem encounter on like those SD cards and stuff.... if your only trying that, theres a switch on the card it self, push it the other way.
if that isn't it... im not too 100% sure then. Could be something in your registry. those reg fixes arn't the best solutions lol.
But uh i found this on google,
1.) insert your usb storage device
2.) open my computer
3.) right click your device and click eject
4.) take out your usb device and reinsert it
5.) try writing stuff onto the drive (just drag like a random file onto it)
6.) if doesnt work... do steps 1-5 again
^ apparently it works and ppl have done it multiple times just to get it to work lol
theres also a registry thing you can do to fix it. (i googled it)
1.) start
2.) type in run and open it
3.) type in regedit (DO NOT MESS WITH THE NUMBERS AND STUFF INSIDE OF THIS!!)
4.) navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrrentControlSet\Contr ol\StroageDevicePolicies
(this is a picture reference incase you do not know how)
http://puu.sh/1VOWJ and on the side look for storage device policies then click it
5.) on the right hand window there should b "WriteProtect". double click the name
6.) a window should pop up. in the box put in the value "0"
press ok and close everything
try now (if it doesnt work, reboot your computer then try again.)
try those