Just went to update my iPhone to version IOS v7 connected to a Windows 7 machine. Received the error “You do not have permission to access the requested resource”. Checked all my versions and updates—there’s nothing wrong.

Here’s the solution:

NOTE: Make sure iTunes is updated and your OS is updated. This is a given.

Delete this directory: c:\Program Data\Apple Computer\iTunes\SC Info

Restart your machine then try again.

This solution worked on Windows 7 x64 with iPhone 4S.