In Inventoria:
-- Open the Options dialog, go to the Other tab, click on Advanced Settings;
-- Check the box marked "Allow Express Invoice, Express Accounts or Copper to synchronize with Inventoria";
-- For the Access Authentication Code, enter an alpha-numeric sequence that is not in use by another business in Inventoria.
In Copper:
-- Open the Options dialog, go to the 'Sync Apps' tab;
-- Check the box marked "Synchronize this installation of Copper as a Client of Inventoria or Copper";
-- Enter the 'Access Authentication Code' being used by the Link-Sync server in Inventoria;
-- Enter the 'Address or IP address of the computer' on which the Inventoria app is running;
-- Enter the 'port number' used by the Inventoria app;
-- Enter a location name used for this business profile (alternatively, click the "Retrieve Locations" button and select the desired location name from the PDL).
Note: Both programs need to be running for syncing to work.