Mac app store will not connect under a managed user account but will under admin. Please help clear this up?

Question

After I have installed OSX Mountain lion I clicked on the app store to buy an app. Only one problem, it says it "cannot connect", I then tried under the admin account and it worked no problem. I log back into the managed user account and disable any parental controls that might be interferring, I try again and it worked. I need the mac app store to work under the managed user with parental controls on. I cleared the iTunes store cache and reset the warnings just to see if that might do the trick but no luck. When the latest update was availble I updated immediatly in hopes of that might fixing the problem but again it did not work.  I would really appreciate if anyone had any ideas on how to help solve this issue.
-Thanks

Answer 1

Back up all data before proceeding.
Step 1
Triple-click anywhere in the line below on this page to select it:
/Library/Preferences/SystemConfiguration/NetworkInterfaces.plist
Right-click or control-click the line and select
          Services ▹ Reveal in Finder (or just Reveal)
from the contextual menu.* A folder should open with an item selected. Move the selected item to the Trash. You may be prompted for your administrator login password. Restart the computer and test.
*If you don't see the contextual menu item, copy the selected text to the Clipboard by pressing the key combination  command-C. In the Finder, select
          Go ▹ Go to Folder...
from the menu bar and paste into the box that opens by pressing command-V. You won't see what you pasted because a line break is included. Press return.
Log out, log back in, and test. If there's no improvement, continue.
Step 2
Reset your computer’s PRAM.