This type of situation can occur even though your Macintosh Powerbook computer's floppy drive is operating within specification. The head mechanism used in Powerbook computers' floppy drives is not capable of recalibrating to the same degree as the floppy drives in desktop Macintosh computers. Therefore, PowerBook computers are "less tolerant" of poor quality disk formatting.
Commercial floppy disks which are duplicated in large volumes at very high speeds generally have lower quality formats. In order to access the information from such disks it may be necessary to format some disks on the Powerbook computer. Then duplicate the commercial software from the original disks using a desktop Macintosh computer and disk duplicating software, such as Apple Disk Copy.
In order to confirm that the Powerbook floppy drive is operating within specification try formatting a disk on the Powerbook. If it can consistently format disks and consistently read them, it is probably operating normally.
This article was published in the Information Alley on 18 October 1996.
Article Change History:
18 Oct 1996 - Added Info Alley publication information.