DVDRAM formatting doesn't work




I have a LG GSA 4040 DVD burner with DVDRAM driver installed. After rebooting the system, everything is fine. If I insert a new DVDRAM, I can format it using DVDForm (or right click -> Format). After formatting and writing to the DVDRAM (with explorer) and inserting a new DVDRAM, formatting does not work anymore. DVDForm says the drive is “in use”. Only reboot solves the problem. What is wrong?

Many thanks for tips,