Invalid or Non-System Disk error

Updated: 11/13/2018 by Computer Hope

Non-system disk error

Floppy, CD, or USB device in computer that is not bootable

Verify that no floppy diskette or CD is currently in the computer. If a diskette or CD is in the computer that is not bootable, your computer may try booting from it and cause this error message.

If you have any USB devices that store information (e.g., thumb drive, iPod, MP3 player, etc.) disconnect these devices from your computer temporarily.

CMOS setup is not properly configured

  1. Verify that your hard drive is set up and detected properly in CMOS setup. Your computer should list a hard drive installed either under the main page or the drives page in CMOS setup. If CMOS indicates the drive is not installed or not detected, skip to hard drive is bad or not connected properly.
  2. Verify the boot options are properly set in CMOS, almost all CMOS setups should contain options specifying how your computer boots. For example, most computers should have their boot options set up similar to the example below.

     - Floppy drive
     - CD drive
     - Hard drive

  3. Reset your CMOS to default values. Many CMOS setups allow users to reset the values to the default settings (usually F10 key). If you've tried the above options without success, try resetting the CMOS.

Hard drive does not have bootable files on it

The or other bootable file may be missing from the hard drive. Follow the steps below to possible resolve your issue.

Windows 95, Windows 98, and Windows ME users

  1. Boot from a bootable floppy diskette.
  2. At the A:\> type fdisk <press enter>
  3. If you receive the error message "no fixed disk present," read hard drive is bad or not connected properly.
  4. If you can get into fdisk, choose option 4 to display the partition information. In the partition information, if the System is listed as FAT16 or FAT32 then continue to step 5. If you have a message indicating no partitions defined, no information is on your hard drive and you need to create a new partition. See the fdisk command page for additional information.
  5. If you see FAT16 or FAT32 in fdisk press the Esc key until back at the A:\>
  6. Once at the A:\> type, sys c: <press enter> (only do this command if you are using the same operating system that this diskette was created on).
  7. If you receive "Bad command or file name" and not "System Transferred" and the command was typed in properly get a bootable diskette with the file
  8. If system was transferred successfully, reboot the computer and issue should be resolved.

Windows 2000 and Windows XP users

  1. Boot from either your ERD, your bootable Windows CD, or your bootable restore CD.
  2. Once loaded choose the Repair Windows option. If you're able to repair Windows, remove the disks and reboot the computer.

All users

If your operating system is not listed above or the above steps did not resolve your issue, you can also try erasing the hard drive and starting over.

The hard drive is bad or not connected properly

If you have tried the suggestions listed above but you're still encountering the same issues, check the connections to the hard drive itself. If the drive was recently installed, or if the computer was recently moved, it's possible the connections have become loose.

Unfortunately, if all connections are set up properly and all the above recommendations have been attempted, it is likely that the hard drive is bad and it needs to be replaced.