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"Missing Operating System" and "No ROM BASIC" Error Messages

This article was previously published under Q80304
Retired KB Content Disclaimer
This article was written about products for which Microsoft no longer offers support. Therefore, this article is offered "as is" and will no longer be updated.
When you start your computer, you may receive one of the following errormessages:

  • Missing Operating System
  • Non-system disk or disk error
  • Boot error Press F1 to retry
  • Invalid Media Type
  • Hard Drive Controller Failure

Missing Operating System

This error occurs when the boot record signature of the master boot recorddoes not match a certain value at a certain location. In this case, theboot sector is invalid and the computer cannot boot. This error can alsooccur if there is no active partition defined in the partition table.

Non-System Disk or Disk Error

This error is generated by the computer's BIOS when the boot sector ormaster boot record of the boot drive is damaged or missing. This error canalso occur if the boot device has been improperly configured in the BIOS.In this case, data in the partition may be valid and undamaged, but thereis no bootable partition.

NOTE: This message also occurs when a non-bootable disk is left in drive Aduring startup. If you receive this error, make sure that there is no diskin drive A and restart your computer.

Boot Error Press F1 to Retry

This error is generated by the computer's BIOS when the hard disk ismissing a master boot record or boot sector, or when there is a problemaccessing the boot drive.


If there is no active partition defined, the master boot record returns anerror to the BIOS. In some cases, the master boot code attempts to go toROM Basic when no bootable disk is found. Since some computers do not haveROM Basic, they display a NO ROM BASIC or other error message. The messagedisplayed is dependent upon the computer's BIOS.

Invalid Media Type

This error message is displayed when the boot sector of a definedpartition is damaged. The error message is normally received using a newpartition that has not been formatted. However, if the boot sector isdamaged, the partition may appear unformatted to the operating system,and this error message is generated.

Hard Disk Controller Failure

This error message indicates either the hard disk controller has failed,the hard disk controller is not set up properly in the BIOS, or thecontroller cannot communicate with the attached drive(s). In this case, donot perform the troubleshooting steps below. Instead, consult thedocumentation included with your computer or contact the computer'smanufacturer for more information.
Each of the error messages listed above may indicate problems rangingfrom improper hardware configuration to damaged hard disk partitioninformation. The following steps can be used to help resolve the problem.However, if these steps do not resolve the problem, please contact yourhardware manufacturer or have the drive serviced by a qualified serviceprofessional.

  1. Start the computer using the Windows 95 emergency boot disk (EBD) or using a bootable MS-DOS disk that contains Fdisk.exe,,, and Scandisk.exe (MS-DOS versions 6.2x only).

    If your computer does not start from drive A, or if you receive an error message similar to one listed above when you start from drive A, please contact the computer's manufacturer.
  2. Use Fdisk.exe to view the partitions on the hard disk by performing the following steps:

    1. Run Fdisk.exe from the EBD or bootable MS-DOS disk.

      NOTE: If the hard disk was not partitioned using Fdisk.exe, use the appropriate third-party partitioning software to view the hard disk partition(s). For instructions on using the third-party partitioning software, please consult the software's documentation.
    2. Select option 4 (Display partition information).
    3. If the partitions are listed, make sure that the bootable partition is defined as active (look for an uppercase A in the Status column.)
    4. If there are no partitions listed, use Fdisk.exe to establish new partitions and then use to format the partition you want to boot from.

      WARNING: When you use Fdisk.exe or to create new partitions or format the drive, you lose any data on that drive or partition.
    5. If all the partitions appear in Fdisk.exe, and one is defined as active, proceed to the next step.
  3. Run the SYS command on the hard disk from the EBD or bootable MS-DOS disk. For example, type the following command:
    a:\sys c:
    If you receive the message "System Transferred," remove the disk from drive A and restart the computer. If you receive the same error message after you restart your computer, your hard disk may be configured improperly or damaged.

    If you do not receive the "System Transferred" message, or if you receive an error message, run ScanDisk from the EBD or bootable MS-DOS disk (MS-DOS version 6.20 or later) to check for physical damage on the hard disk by typing the following command:
    a:\scandisk c:
    If you are prompted to perform a surface scan, choose Yes. If ScanDisk reports physical damage on the hard disk, have the hard disk checked by a qualified service professional.
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Article ID: 80304 - Last Review: 11/16/2006 13:41:26 - Revision: 2.1

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