JVM debug port 7779 is in use

I am using RAD 8. When I start the server in debug mode, it displays a error message states that JVM debug port 7779 is in use. I had this problem many times as I know this port was used by RAD. So I had to stop the process with image name "Java" under Window Task Manager>Processes. But however for the first time I face this issue without no such "java" process running in Window task manager. In my knowledge none of the IBM product does use this port presently. I have even tried to restart my system and started the RAD, but still the issue remained same.

I deleted the profile and re-created a new one. After that I started in debug more. And it started without any error.

But again to get all the resources imported from my friends server, I got his .car file. After importing this I started the server and got the same issue. Now wondering what could cause this port used issue when just importing the .car file.

1. Can you please tell me how to know which application uses this port and how to stop it
2. Is there a way I can change the debug port while creating the server profile? I tried to see the debug port in profile creation but didn't find anywhere.

Friends please share me if you have any input. I will share if I get the root cause of this

I got the issue fixed. I was able to change the debug port number. Below are the steps

1. Start the server in normal mode (ctrl+Alt+R).
2. Go to application server configuration window.
3. Click on Debugging service under "Additional properties"
4. Update the JVM debug port e.g. 7780
5. Update JVM debug arguments for address e.g. refer the address=7780 for the below entry

-Dcom.ibm.ws.classloader.j9enabled=true -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=7780

6. Click on apply
7. Click on save
8. Stop the server
9. Start the server in debug mode (ctrl+Alt+D).