Error "Tableau Server Load Balancer Requires Port 80" Using IIS

Published: 01 Jul 2013
Last Modified Date: 02 Mar 2018


When starting Tableau Server, the following error might occur:
*** Tableau Server Load Balancer requires port 80,
in use by process 4.

*** Error: Tableau Server cannot start due to blocked ports.

Running tabadmin status -v shows server status as Degraded and that Apache Load Balancer was not started.

Netstat shows that port 80 is being used by the system PID 4 (Windows kernel process).


  • Tableau Server
  • Microsoft Internet Information Services (IIS) or IIS Hostable Web Core


  1. Remove or disable IIS.
  2. Restart Tableau Server.


IIS blocks port 80. 

Additional Information

Running IIS (or any other web service) on the same computer as Tableau Server is not recommended as it can result in port conflicts as noticed from the error "Tableau Server unable to start blocked ports".
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