To fix the permissions you have 2 ways to follow :
1) right click iside the wwwroot dir and then select the 'Web Sharing' Tab, next if you have no alias added and select the permissions to read, write and select to allow scripts to be executed.
the other way is to go to control panel, select administrative tools, intenet information services => then expand the tree and right click on the Default web Site there you go to 'Home Directory' Tab => and under read permission there is write, select it !
and Voila!