Don't think you're missing anything – it's just that the H8000 is not seeing the card.

It could be an issue with the card, with the adaptor, or with the stuff on the card. First thing to try is to get a new card, 1G or less and do not format it.

But, I wouldn't bother. We strongly advise people not to perform an upgrade unless they need to. Any upgrade has a small but real risk of problems.

Many times a change in version number results from a change for manufacturing or test purposes, which will have no benefit to an end user. In your case, the change from 5.6 to 5.61 was to support a newer display – if your unit runs with 5.6 it has the older display and 5.61 will do nothing for you.