Have a problem with SanDisk Ultra 64GB Micro SD XC I card. It is disappearing like Harry Houdini from SP3, after that it has to be reinserted again to work for while and vanishing again from the system. Do not have any problems with Kingston 2GB Micro SD card. 64 GB card is not loosing any data. Uninstalled and reinstalled drivers, reset SP3 to factory settings, no fix.....