What is port conflicts?
A computer has 65,535 ports like doors for communicating, and each port is assigned a number called a port number. When computers communicate with each other, data is exchanged using ports with the same number. The port to be used is determined by the communication method and software. (e.g. Apache uses number 80, and MySQL uses number 3306.)
However, there are some services that use the same number as other services, so if Apache is using a port number 80, this port cannot be used by anything else. This is the state of port conflicts.
How to check port conflicts
I was using XAMPP when I got port conflicts, so I checked Netstat in XAMPP.
Click on the Port, it is arranged in numerical order.
If there is a same number as the service you want to use, you need to terminate the another service that is using the port. Thereby you can use the service you want to use.