Hope someone is still reading this 
I've been having problems with Windows Explorer taking a really long time to load up. In order to troubleshoot, I wanted to change EVERYTHING back to default MS.
I still am using IP 4.1 and tried to apply Windows default icons. After much mucking about with rebooting/"repair icons", "rebuilding icon cache", etc, I have managed to get all icons changed correctly, EXCEPT for the contents of the folder "C:\" All sub-folders are correct and all folders/sub-folders everywhere on all disk drives are correct, just the icons for "C:\" are not. I have repeated 3 times, all the mucking about stuff to no avail.
Turns out I can fix them by clearing their 'read only' attribute, going to 'change icon>restore defaults>apply' using the context menu for each folder. GRRR...Ok, apparently that only works on a couple of the folders. 
Not sure how, because the last thing I did prior to this post update was reboot, but... uninstalled WB and rebooted. All icons are displaying correctly.
I really shouldn't have to do that.
Thought I'd pass this along.
David