How to fix "Cannot connect to already running IDE instance." error when launching PyCharm?
The error informs you that you cannot launch PyCharm because another instance of it is already running. The error also informs you that the process ID (PID) of this instance is 5095.
So to launch PyCharm, you have to kill this running instance (which is probably a crashed instance) using the PID provided by the error. To do that open a terminal and run:
kill -9 5095
If you prefer a graphical way of killing the specified PyCharm process, you can do it as follows:
Open System Monitor.
Go to the Processes tab.
Search for "5095". This should only list this PyCharm process.
Right-click on the process and select Kill.
In the pop-up window click Kill Process.
Then try to launch PyCharm again. It should open properly.