Each disk drive uses an identification letter. "A:\" represent a floppy disk drive used for 3.5-inch disks. This error occurs when you try to access a disk in the "A:\" drive, and the computer cannot find the disk or the drive.

How do I correct the error?

1.     Verify the disk drive is connected properly, especially if it is plugged in outside the         computer case.

2.     Verify there is a valid formatted disk in the drive.

3.     Try another disk. If another disk functions properly the original disk might be
        damaged, or it might not be formatted. If another disk gives the same error, the         problem might be in the drive or in the connection.