If I add a "client.stop();" right before the "webFile = SD.open("index.htm");" then the file is found on the sd card, obviously this means I can no longer push the page out to the browser but... it seems to mean that the EthernetClient is either holding SS OR MISO for some reason?
or is there a flaw in my logic?
I welcome anyone's thoughts on this.... its driving me crazy and I need to solve this.