    System: XPS 13 9380, but 2018 XPS 15 has the same issue Sandisk extreme plus a2 128gb cards not seen, even under fdisk.  Cards work with an external usb reader.  Per other owners, cards will read under windows.  Sandisk Ultra A1, Lexar, PNY, Monster all function with internal reader. Appears to be a driver issue, does anyone know of a source for updated drivers/modules? Extreme® PLUS microSDXC™UHS-I CARD is SDXC and EXFAT EXFAT is not supported by default When you plug in the USB drive your system will show a message like this:Error mounting /dev/sdb1 at /media/linuxize/USB: unknown file system ‘exfat’   exFAT (Extended File Allocation Table) is a proprietary Microsoft file system optimized for flash memory devices such as SD cards and USB flash drives. It was designed to replace the old 32bit FAT32 file system that cannot store files larger than 4 GB. exFAT file system is supported by all the latest versions of Windows and macOS operating systems. Ubuntu, like most of the other major Linux distributions, doesn’t provide support for the proprietary exFAT filesystem by default. To be able to mount exFAT filesystem on Ubuntu you’ll need to install the free FUSE exFAT module and tools. Before installing the packages make sure the Universe repository is enabled on your system. Open your terminal either by using the Ctrl+Alt+T keyboard shortcut or by clicking on the terminal icon and type:   Once the repository is enabled update the packages index and install the exfat-fuse and exfat-utils packages using the following commands:  
System: XPS 13 9380, but 2018 XPS 15 has the same issue Sandisk extreme plus a2 128gb cards not seen, even under fdisk.  Cards work with an external usb reader.  Per other owners, cards will read under windows.  Sandisk Ultra A1, Lexar, PNY, Monster all function with internal reader. Appears to be a driver issue, does anyone know of a source for updated drivers/modules?
microsd reader not reading a2 cards in ubuntu