Sudoku displays grid of game but cannot print it

Until a few weeks ago I could open the Sudoku game and print puzzles to solve later. Now I can generate a puzzle but cannot print it. When the Print button is pressed it appears to go through the usual procedure, but a Print Sudoku notice appears in th top panel and nothing is sent to the printer. This happens using another computer with a different printer, so it must be due to a change in the program itself.