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How do I configure the firewall for the network version of TaxCalc?

Article ID: 2056
Last updated: 24 Mar, 2020

The following ports must be open to allow access to the discovery service and the database, and should suffice for most installations.

Server Side

Incoming Rule

  • discoveryservice.exe Port 3838 (UDP)
  • postgres.exe Port 5432 / 5433 (TCP)

Outgoing Rule

  • discoveryservice.exe Port 6178 (TCP)
  • postgres.exe Port 5432 / 5433 (TCP)

Note: If users on a Cloud Server installation type are unable to connect to the DB, please ask them to make sure that port 38476 is open on the router. 

IMPORTANT: From version 4 of TaxCalc (November 2016) it is necessary to add the port 5433 (TCP) and 5432 as TaxCalc has updated the version of PostgreSQL used. This means that on any given installation the port could be either 5432 or 5433. If you are not sure which one is in use add both.

Client Side

Incoming Rule

  • taxcalchub.exe Port 5432 /5433 (TCP)

Outgoing Rule

  • taxcalchub.exe Port 5432 / 5433 (TCP)
  • taxcalchub.exe Port 6178 (TCP) 


  • By default PostgreSQL uses port 5432 or 5433 (TCP) (November 2016 onwards), although this can be customised. 
  • The discovery service, that accepts multicast messages from clients to the server, listens on Port 3838 (UDP).
  • The discovery service on the server will then respond to the client on Port 6178 (TCP), outgoing from the server, incoming to the client.
Article ID: 2056
Last updated: 24 Mar, 2020
Revision: 8
Views: 5706
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item Cannot connect to DB - Server machine

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folder Technical -> Firewalls and Proxy Servers