Question about WD My Book (500gb)

Hey ppl, my WD hard drive was working fine for 7 months, today i tried to copy/paste a file from my C: to WD and it always wants me to ‘perform it’? When i click ‘OK’ it says that i will lose all my data, is there a way to fix it or convert it to NTFS without losing data? Thanks. I got this WD