Maybe it was not properly shut down the last time you stopped the application. Did you check your task manager? Or did you try to turn your PC off and on again? (I heard turning it off and on again is magic)
Possible causes:
Cause 1: Multiple instances of Mendix Studio Pro are running at the same time and are using the same port. In our case port 8090.
Possible solutions:
Cause 2: An instance of Mendix Studio Pro has crashed, but a process is still listening to port 8090
Possible solutions:
Stop the process
Let's take a closer look at stopping the process that is still listening to port 8090 with an example.
In this example Mendix Studio Pro crashed. We are opening a new instance of Mendix Studio Pro. When we start the application we get the Warning with message “It appears that port 8090 is already in use...”. In this case we can stop the process from the command line by following the steps below.
Step 1: Open Command Prompt
Note that the values in the example will differ from your values. Do not just copy the values from the example
Step 2: Find what process is still listening to port the port
netstat -ano | findstr :<PORT>
Eg. netstat -ano | findstr :8090
Step 3: Stop the process
Eg. 29565
taskkill /PID <PID> /F
Eg. taskkill /PID 29565 /F
Step 4:
Eg. netstat -ano | findstr :8090
Now you can restart you application and it should run on port 8090.
I hope this helps :)
Solved! Good old pc restart.
that error can also happened when you are working on multiple mendix project, and run the projects at the same time.
You can run multiple projects at the same time if you edit the port that you use in the project setting
(setting → edit configurations → change the runtime port to 8081 for example).