All the info in here has been brilliant, i have an on-going issue that i can't seem to fix though.
I have now gone through 2 cards, the first one thinking it was broke so i sent it back, and my unit is doing the exact same with my new card.
When i got my first card which was a sandisk ultra 64gb sdxc card, i thought it was originaly a bad card as my unit wouldn't see it, plus when i put it into my laptop and formatted it, it only showed as 32gb.
i exchanged that card for basically the same one, but it said made for android on it.
I put that straight into my unit when i opened it and that said the same thing on my unit, can now safely remove card, and when i went to settings > storage, there was no sign of a card, it just said mount card, and if i did this, it would say preparing card then a little after say i can safely remove it again and still show nothing.
i have now put this card back on my laptop and formatted it as fat32 (as i thought this one was going to be already seems it says its made for android devices), and again, it shows on my laptop as only 32gb and not 64gb, the file system is fat32 as well.
i have seen screen shots of people using this card in a 10.1 and their storage does show as 64gb.
i have tried using hp format utility and guiformat to format as fat32 (both show on unit but only as 32gb), i have tried using windows 7 formatter to format as exfat (which wont show in my unit), i have also tried sdformatter 3.1 which also doesn't seem to get my 64gb to show.
can anyone help, i surely couldn;t have got 2 bad cards?
james