A client has a Pix 515E which they don't know the enable password for. Their engineer attempted to perform a password reset but used the 6.3 utility on 7.2(2) code. All went well until the reboot when the system would not come back up... said the .bin could not be found and continuously rebooted... got the call for help and I TFTP pix722.bin, rebooted, it comes up, and passes traffic. However, during the boot process the following warning appears:
"WARNING: BOOT variable added, but not a valid image flash:/pix722.bin
*** Output from config line 23, "boot system flash:/pix72...""
Additionaly, enable mode is still not accessible.
When you TFTP the image to firewall in monitor mode, it opens up in memory first to boot, doesnt exist in flash. Thats why you see this error. Entering enable mode and copying the image with the following command to flash will solve the issue
copy tftp://tftpserveripaddress/pix722.bin flash:/pix722.bin
But for running above command, you need enable password. First you should reset the enable password. Follow the below guide
Download the 7.0 bin, and apply the steps below PIX without floppy.
After you set your enable password and copy the image, dont forget to run
Another possibility is a corrupt image.