If you need to re-print checks in CORE for some reason, go to the Checks > More > Print Checks screen. You will see all your checks based off of the Bank Account chosen. Then select the checks you want to re-print and click Actions > Batch Update and set the 'To Be Printed' value to true. You can then go ahead and reprint them. If it is a single check, find the check that needs to be reprinted and provide the check number and style at the top. Be sure the alignment settings are correct before you reprint the check. Check CORE Help for details on printing checks.
If you want to reprint checks with the same check number, you must first void and delete the existing check. Check CORE Help Center for details.