There are a few reasons why you might get a "connection refused" error when trying to connect to MongoDB:

• The MongoDB server is not running.
• The MongoDB server is not listening on the port that you are trying to connect to.
• The firewall is blocking the connection to the MongoDB server.
• The MongoDB server is not configured to allow connections from your client.

To resolve the "connection refused" error, you need to make sure that the MongoDB server is running, listening on the correct port, and configured to allow connections from your client.

Here are some additional tips for resolving the "connection refused" error:

• Check the status of the MongoDB server: You can use the ps command to see if the MongoDB server is running. If the MongoDB server is not running, you can start it with the mongod command.
• Check the port that the MongoDB server is listening on: You can use the netstat command to see what ports are in use on your computer. If the MongoDB server is not listening on the port that you are trying to connect to, you can change the port that the MongoDB server listens on in the mongod.conf file.
• Check the firewall: If you are using a firewall, make sure that it is configured to allow connections to the MongoDB server.
• Check the MongoDB server configuration: Make sure that the MongoDB server is configured to allow connections from your client. You can check the configuration in the mongod.conf file.