Nes SD cards not detected

[mvtijam]

I have a number of new SD cards but are not detected. If I'll insert my old SD card it's detected even I have emptied the files. Right clicking to reformat is not working either, can someone help?

 

[mavroxur]

Is the new card SDHC? Some older readers will read SD but not SDHC. SDHC cards are typically 4GB or greater.