Cannot Use DISKCOPY Command on Identical 3.5-Inch Disk Drives

• Microsoft Windows 95

SYMPTOMS

When you try to run the DISKCOPY command from the Run command on the Start menu to copy from one 3.5-inch floppy disk drive to another identical drive, you may receive the following error message:

   Unrecoverable read error on drive A: side 0, track 64
   Unrecoverable write error on drive B: side 0, track 64
   Target diskette may be unusable.

RESOLUTION

To work around this behavior, use any one of the following methods:

• Run the DISKCOPY command in MS-DOS mode. To do so, follow these steps:

  1. Click the Start button, and then click Shut Down.

  2. In the Shut Down Windows dialog box, click "Restart the computer

        in MS-DOS mode," and then click Yes.
  

  3. At the command prompt, type the DISKCOPY command you want to use.

        For example, type:
  

           diskcopy a: b:
  
     4. When the copy operation is finished, type the following line and
        then press ENTER:
  
           exit
  
  

• Disable protected-mode support for the floppy disk controller. This causes the floppy disk drives to operate in MS-DOS Compatibility mode. To do so, follow these steps:

  1. In Control Panel, double-click System.

  2. Click the Device Manager tab.

  3. Double-click the Floppy Disk Controllers branch to expand it, and

        then double-click Standard Floppy Disk Controller.
  

  4. Click the Original Configuration (Current) check box to clear it,

        and then click OK.
  

  5. When you are prompted to restart your computer, do so.

• Manually copy the information from the source disk to the destination disk.

STATUS

Microsoft is researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

This problem does not occur on computers with one 3.5-inch floppy disk drive and one 5.25-inch floppy disk drive, or on computers with two 5.25- inch floppy disk drives.