If it's been formated with NTFS Android won't recognize it. Put it in your laptop and select FAT32. After you format it put it in your Note 2 and it should see it and you will be able yo format it for Android.
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What is the brand name of the card?
What size is the card?
What class?
Did you try the long format FAT32 on your laptop/computer?
What OS is on your computer?
Did you go to the Sandisk website and try the troubleshooting steps? I hope the SD card isn't defective. Sandisk had major problems before and the Note 2 was one of the phones that had issues w/Sandisk cards. How old is the card?