I have a couple 7206VXR routers (one production and one spare) that are giving me this message when I do a sho flash command. I know the slots work because I powered the spare down, installed another ATA flash disk in slot0, powered up, and was able to read it via sho flash. I powered down, reinserted the original disk, powered back up, still no access. I know you're not supposed to have to power down and up to replace Flash disks but with 2 bad ones I didn't want to risk a 3rd. These disks were made in 2000, well before the 2005-2006 Field Notice references for flash disk defects.
I have verified that the spare is booting from the "back up" IOS instead of the flash disk. The production unit hasn't been rebooted, yet. I do have the ability to boot via TFTP if necessary.
Any options besides buy new and reload?