Hi, Whatever I do, whichever dedicated app for file transfer to SD card I use (most notably Link2SD), invariably produces failure. In Link2Sd, with movable apps, I get an error message: "Failure / LINK2SD could not obtain root access / If you have root access, make sure you respond "Allow" or "Grant" to the superuser request." Now all this is perfect gobbledigook to me. First, why would such a simple device as a memory card in any computer behave that way: being seen by the machine, but not allowing it to be read? Second, what is "root access"? Third, if someone explains to me how to obtain that mysterious root access, how do I respond to the "superuser" request. Finally, what is "superuser". No documentation mentions any of these things... If anything, Android in all its forms is under-documented. Thanks for any answer, which will enable to accomplish that simple operation: transfer most if perhaps not all files to the extra memory I dearly bought. Best and thanks.