Help, MFC Printer all in one, ink LC51 bk. won't print.?

I need help my MFC printer all in one will only print in colors and not in BLACK, I have new cartridage and it won't print black, the printer shows that it if full. What is the problem? It uses LC 51 cartredages. Therefore anything I faxed is bearly readable if at all.Help, MFC Printer all in one, ink LC51 bk. won't print.?
Please re-install the ink cartridges and re-install your printer driver.


Hope it can works for you.

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