HI SebastianZ,
Second Link are working..
How to make USB drives read-only with Symantec Endpoint Protection using Application and Device Control
http://www.symantec.com/business/support/index?page=content&id=TECH95813&actp=search&viewlocale
Check this Fourms
https://www-secure.symantec.com/connect/forums/sep11-application-device-control-problem-usb-set-read-only-w-write-exemptions-does-not-work
Check this thread https://www-secure.symantec.com/connect/forums/ro-access-using-adc
https://www-secure.symantec.com/connect/forums/usb-device-read-only
https://www-secure.symantec.com/connect/forums/how-prevent-reading-files-sepm-121
https://www-secure.symantec.com/connect/forums/help-ro-access
#Edit..
Due to IE issue My comments not showing proper i have edit my comments