Check the following.
- Make sure your network connection is enabled.
- Make sure you are on the same network environment as the smartphone you are trying to connect to.
- Make sure the IP address is set correctly.
- Ensure that communication on the port (12251) specified by the mocopi link is not prohibited.
- Make sure that the mocopi link app on your smartphone shows the "Waiting for connection from the mocopi app on your PC..." screen.