RADAR repeatedly asks me to insert the Data DVD although it is already inserted
Reason:
The Roxio software, which is used to burn CDs and DVD, installs a concurrent UDF Reader which fails to read DVDs which are not created by the Roxio UDF file system. To check if this is the reason, insert the Data DVD and open My Computer (Windows explorer). Right click on the DVD and choose properties. If the file system is reported as UDFRDR, then you need to uninstall Roxio.
Solution:
Go to Start - Control Panel - Add or Remove programs (or Programs and Features under Vista) and select the Roxio software (Easy Media Creator, Easy CD Creator...) and uninstall it. You do not need to uninstall the Cineplayer.
Open My Computer (the Windows explorer) and navigate to the folder C:\WINDOWS\SYSTEM32\drivers
If you find any of these files:
udfrdr.sys
udfreadr.sys
udfreadr_xp.sys
rename them to udfrdr.sys.deactivated, udfreadr.sys.deactivated and udfreadr_xp.sys.deactivated.
Reboot your computer. Insert the DATA DVD, open My Computer (Windows explorer) and right click on the DVD. The file system should be reported as UDF now and you should be able to browse through the content of the DVD.