HP L7680 gives error ink in cartridges depleted can not printbut they are full

I had this problem recently after replacing the yellow ink cartridge. After much wrangling with HP, they sent me a new cartridge (since it's date code was not expired) and that seemed to fix that particular issue. You might also try getting a replacement cartridge from the vendor that sold you the one in question since it's likely to be faster and less painful than going to HP directly.