1. You did not deploy your code on the remote server.!
Make sure that the recent edition of your code is deployed on the server. You can always deploy your code from Tools -> Deployment -> Upload to ..., or by using Ctrl + Shift + Alt + x.
For setting the deployment path, Go to File -> Settings -> Build, Execution, Deployment -> Deployment, and enter a remote sever details as your deploying machine.
In the Mappings tab, make sure that the deployment path is defined somewhere on the server where you have permission to read and edit files there.
2. You do not have the permission to read and change files on your deployment path at the remote server.
Go back to File -> Settings -> Build, Execution, Deployment -> Deployment, and change deployment path on the Mappings tab.