Epson Stylus Pro 7450 User Manual page 177

Nozzle check pattern examples:
good
head cleaning necessary
If you find that any dots are missing from the test lines in the
pattern, you need to clean the print heads. Press the Menu r
button for more than 3 seconds or access the Head Cleaning utility
software. For Windows, see "Using the Printer Utilities" on page
31. For Mac OS X, see "Using Printer Utilities" on page 53.
177
The Control Panel