I have a Sony VAio pcv-rs720g running windows XP home ed. When I put a disk in the floppy drive it tells me that there is no disk in the drive and to insert one. I've tried a dozen disks. Also I went to device manager and deleted the floppy controller and reinstalled it, no help. I reset the AMI BIOS to default, no help. I tried a new floppy controller cable and new floppy drive and it still fails. It appears to me that it is a motherboard problem. Correct if I'm wrong. Is there any other test that I should perform?

Could be the drive controller. You would have to take it tech to have the chips tested. An alternative would be to get an external USB floppy. Probably cost less than the tech.

Unfortunately it didn't help. We changed out the motherboard and it still won't work. Obviously something in the operating system or some software must have benn corrupted. The problem is what is it? I am buying an external USB floppy drive rather than having to restore the hard drive back to factory defaults and then have to put all my programs back in. It just irks the Hell out of me why it won't work.