Scenario 1

Your board is currently 7.3 to 7.5.5 version

and

you _JUST_ want to patch.

go to members area and download the patch for your board and simply upload those files and you are done

Scenario 2

Your board is currently 7.0 to 7.5.5 version

and

you not only want to patch, but you really want to upgrade to latest version.

go to members area and download the full install of the latest 7.5.6p and run the upgrade.php script.

you are now not only upgraded, but you are _ALSO_ patched.

Scenario 3

Your board is 7.5.6 latest version ( not patched )

and

you want to just be safe and get patched

go to members area and download the patch for 7.5.6p and simply upload those files and you are done

That's all the scenarios

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SD