The USPS provides free Early Warning System (EWS) data to prevent matching errors due to the age of the address information in the .gsd files. The USPS creates a new EWS data set each week that you can download from the USPS website (https://postalpro.usps.com/cass/EWS).
To install the Early Warning System (EWS) database rename the database file from OUT to EWS.txt and place it in the same folder as the primary database.