Find out what's blocking port 80 / 443 on Windows and stopping Qlik services from starting

[Sonja_Bauernfeind]

It is not always obvious what process is currently using a specific port. This can make identifying why a Qlik service is not starting difficult. 

This is how you find what task that is currently listening on the default HTTP-port 80 or HTTPS-port 443. This can be applied to any port.

Open the Command Prompt (cmd.exe) and execute the following:

Step 1 -  Find PID of program:

netstat -ano | find "443" or netstat -ano | find "80"

The list could be long. Look for something ending with :443 or :80 in the second column. Get the pid from the right most column (e.g. 37400)

Step 2 -  Find the name of the task with the resulting PID:

tasklist /svc /FI "PID eq 37400"

The output should give you the name of the task that is blocking your port.

Step 3 - If the PID turns out to be PID 4 or something else that displays "Can not obtain ownership information" use:

net stop http

This will show you any additional services that are dependent on 80/443