Problem with cd drive & dvd drive

[etones]

hi, i have a problem with both my cd and dvd drive. when i enter my computer 4 icons appear for the drives even through there are only 2 drives. and i cant open or access the drives in my computer. there is a disc in the cd drive but i cant access it or open the drive. also having some problems with my net drive sometimes when i enter the net drive to open a file, it displays no files, but other times it displays all of them why do you think that is

edit - also when i was creating a cd lastnight it kepted failing at 47% using nero express.