Few days back I had an issue with my Toshiba laptop not reading my SD memory card. When checked online many has reported this issue with Toshiba laptops. The issue is not related to hardware at all, it is with the driver.
This issue of Toshiba laptop not reading SD card is generally found in new laptops or in laptops in which a new OS is installed. The issue is because your Toshiba laptop is not having a driver to read the SD memory card. Install one and you will be fine.
Go to Toshiba website > Support > Laptop Computers > Enter the model or serial number of your laptop > Drivers and Updates > Card Reader > Download any one of them > Install
Restart the laptop and put your SD memory card back in, it should work fine.