Was the tablet restarted (turned off and back on) or "Reset"? If it is the first one, that shouldn't effect a SD card. However, if it is the second one, and the SD card was set as "Internal" storage before the "Reset", then all the data on that card is no longer accessible. There is no way to get it as the card was encoded when made "Internal" storage rather than the standard "External" storage. Making it unreadable by any device other than the one it was in at the time of the conversion. And, when you "Reset" any device, you change it, making the connection to the cards encoded data gone.