This method can only be used when the Year is the only change as is the case in 2013 to 2014. Keep in mind, if you are on Employee Email Suite version 12.0.10 or higher the system will prompt you when you send W-2 Statements that your report year is not correct if you only update the report and do not install the year end update.
Navigate to the Microsoft Dynamics folder, then select the Data folder, then select the W2-Attach folder. In the folder you will see the file W-2 Instructions.pdf. Replace this file with the 2014 version from the Integrity Data website download page for 2014.