Unable to mount blank dvd-r disk
my dvd writer says location id already mounted i only have one I have used a usb writer bu the onboard one will not mount
I am not certain that I fully understand your question. Technically, you can't mount a blank dvd-r disk as it does not contain a file system! The dvd device already has a mount point assigned to it (usually under /mnt or /dev). In order to mount a blank cd-rom or dvd, you will need to utilize a disk burning application so that can format the disk and place data onto the drive.
I hope that this helps to send you in the right direction...
Good luck & have fun!