When attempting to install WinPE 2.1 in the PXE Configuration utility (or through the Boot Disk Creator) the error message is displayed "Errror: Windows cannot access the specified device, path or file. You may not have appropriate permissions to access the items." However, the console user has administrator rights on the server.
The issue is caused by Internet Explorer "Enhanced Security". The installation of IE Enhanced Security can be confirmed in the Windows "Add or Remove Programs" control panel by clicking on the icon for "Add/Remove Windows Components".
Right click the .exe file for WinPE 2.1 and choose Properties. Click the option for "Unblock" next to the message indicating the file came from another computer and may be blocked.
Deployment Server 6.8 through 6.9 SP5 MR3