Distressingly, many of the tested cards were mediocre to poor on that metric, which may explain why running updates on Linux running off SD cards can take a very long time. May want to see if the cab file listed can be ported to HD Navionics Update Card. I still don't remember CF-cards having hardware copy protection as part of the specification and it makes sense that they might be easier to copy. In the HD7 General forum I found a method using the HD7 itself that actually worked and I unlocked and salvaged 3 locked cards last night
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