keep getting error when opening dvd

[goldenvirginia]

it seems most disks i put in my nec3520 get the message,windows cannot read from this disk, it might be corrupted or not using a format compatible with windows,

the disk is a dvd-r backup and it has worked before, even data disks dont play, i updated my firmware a while ago but nothing can play the disk cos its unreadable, is there a programm runing in the background effecting my dvd righter

[Krispy Kritter]

To verify if your burner is working, try a commercial disk. If that works, then most likely there is an issue with your backups(most likely bad media). If a commercial doesn't work, then you most likely have a bad drive.