“Why is my SD card reader not working” may be the most concerned question for these new Windows 10 users. It has a built-in SD card reader but my SD card won’t show up. Hey, my laptop came with Windows 8, but I bought an SSD and downloaded Windows 10 for it. However, lots of users reported their SD card reader not working on Windows 10. Windows 10 is quite an excellent Windows operating system and many Windows users have chosen to upgrade their system to Windows 10. Fix 5: Clean up Virus or Malware on SD Card.Fix 2: Run Windows Hardware Devices Troubleshooter.