Here is what you need to do, Open My Computer on your desktop. Go to Tools then folder options. Click the View tab and scroll to the bottom under Advanced settings and look for "Use simple sharing (recommended)" and take the check mark out of it. Click apply then ok.
Go to the USB drive and open as far as you can on your hard drive. Click double click it then Documents and Settings and then your login name. Once you get an error message, right click on the file and go to Sharing and Security (or Properties) then click the Security tab. Click the Advanced button then click the Owner tab. Look for your login name and tick a check mark for "Replace owner on sub containers and objects" then click Apply then OK.
Back under the Security tab again click Add, then type "Everyone" without the quotes then click Check Names. Click OK. Again back under the Security Tab click once on Everyone and the tick the Full Control under Allow then click Apply then OK.
You should now have access to the entire folder. Good luck.
Cheers
Rob
The answer is always "PEBKAC!