Reference number: CH000402

Boot Record Signature AA55 not found.

Issue:

Boot Record signature AA55 not found.

Alternatively, you may receive such error messages as:

1. Non-System or Non-Bootable Disk.
2. Strike F1 to retry boot
3. OS Loader 4.0
   Boot Record signature AA55 Not found, xxyy Found
   xxyy may vary depending upon the BIOS manufacturer.

Cause:

This issue could be caused by any of the below possibilities.

1. Computer Virus
2. Malfunctioning hardware

Solution:

Overall, the resolution / workaround to this issue would be to recreate the master boot record. However, it is important to note that because of the potential possibility of a computer virus such as the Monkey MBR virus, doing this command could cause possible data loss or additional issues. Verify that the latest version of your virus scanner is installed on the computer and that you have verified no viruses exist on the computer. 

Additionally, you may consider backing up the data on your hard disk drive.

To recreate the master boot record, boot from a bootable floppy diskette and at the prompt type:

fdisk / mbr <press enter>

This should return you to the prompt with no message

Once back at the prompt reboot the computer and the issue should be resolved.

Additional Information:

• See document CH000175 for additional information and help with the fdisk /mbr command.
• Additional information about creating a bootable diskette can be found on our boot disk page.
• See our monkey virus information page for additional information about the Stoned Empire Monkey virus.