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"Checksum error in file flash:/pix721.bin.No bootable image in flash. Please download an image from a network server" error is received after the PIX 500 Series Firewall is upgraded from software version 6.3(3) to 7.2(1)

Core issue

This error occurs due to a corrupted Flash memory.


As a workaround, format the complete Flash and then upload the image again.

Complete these steps in order to erase the Flash memory:

  1. Backup the PIX Firewall configuration and issue a show version command to see  the activation key contained.

  2. Reload the PIX Firewall and interrupt the boot sequence by pressing either the esc or break key. This takes you to monitor mode.

  3. Once in monitor mode, run the TFTP server with the erasedisk622.bin image in the root directory of the TFTP server.

  4. The PIX Firewall now reboots and asks for the activation key. Enter the key that you located in step 1 of this procedure.

    The device goes into ROMmon mode again.

  5. Upload the software pix721.bin. In order to do this, use this same procedure but with the file name as pix721.bin

Refer to Cisco PIX Security Appliance Release Notes, Version 7.2(1)  for more information.

Refer to the PIX Software Downloads page in order to download the latest IOS  image for your PIX Firewall.