To access printer redirects click on the Printers drop down on the main menu and click on Redirects.
Once on the printer redirects page find the record you want to delete and move your mouse over it to reveal the controls and click on the delete button.
After clicking on the delete button you will be prompted to confirm your deletion. If you are sure you want to delete the record click on the "Delete Printer Redirect" button.
The printer redirect will be deleted.