According to the Houston Chronicle, some of the reasons why a printer does not print include a bad connection, software problems and low ink levels. When diagnosing a malfunctioning printer, consider contacting the printer manufacturer for information or visiting a local repair shop for additional help.
Bad connections between the printer and computer occur when a cable is detached or incapable of functioning properly. Reconnect your computer printer to the PC port or substitute a new cable before checking other possible diagnoses of the causes of the printer's problems. If a bad connection is not preventing the printer from printing, software issues may be affecting the printer. These issues can be resolved with the computer's print manager or by the front panel display on the printer.
Sometimes printers do not print because there are too many documents in the print queue. To resolve this issue, access the printer's management software and manually cancel all pending print jobs in the queue. Try reinstalling or updating the printer's driver software to ensure that the software applications are able to send document data for successful printing. Lastly, check the printer's ink cartridge or toner cartridge to determine whether it needs to be replaced.