When the lock tax location check box is selected, DynamicZip schedule assignment will use the following fields in the Address Supplement.
When the lock tax location check box is not selected, DynamicZip schedule assignment uses the address card's city, state, ZIP and country code and only refers to the Address Supplement for the Outside City Limits selection and the geocode to identify the county when it cannot be identified using Zip+4 Option.
This means that if the lock tax location check box is not selected, the card's address overrides the city, state, ZIP and country code on the address supplement. If the Zip+4 Option is enabled and the ZIP includes the +4 extension and DynamicZip is able to identify the county based on the +4 extension, the county so identified will override the county (if any) identified by the address supplement's geocode.
By selecting the lock tax location check box, you can effectively specify a tax location that is not the same as the address on the card. This is especially useful when items are shipped to an address that is not the same as the location where the items will be used and should therefore be taxed.