My USB SD card reader does not work, windows says " J:\ is not accessible" why is this ?

I tried inserting 4 different SD cards into the USB card reader. None of them work. I put the cards into two different cameras. both cameras read them.... So cards are working fine. I plugged in two different USB sticks into the computer and both are working fine ..... SO when I plug the USB card reader and insert... show more I tried inserting 4 different SD cards into the USB card reader. None of them work. I put the cards into two different cameras. both cameras read them.... So cards are working fine. I plugged in two different USB sticks into the computer and both are working fine .....

SO when I plug the USB card reader and insert a SD card windows keep saying need to format the sd card when I say okay format the card. Windows saying failed to format and " J:\ is not accessible" message comes up.... Could this be due to a faulty USB SD card reader ? I can not think why this would happen otherwise ? Windows did do an update but USB Card reader was working after that for like 2 hours

file format Fat32... exFat32... NTFS none seem to be working
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