A Utility Fails to Connect to the Server

Problem: Using a command-line utility such as esp_client or esp_subscribe, you fail to connect to the ESP server.

The command might return this message when it fails:

Couldn't connect to server, XML-RPC Fault(-504)

Utilities affected by this issue include esp_client, esp_cnc, esp_convert, esp_kdbin, esp_kdbout, esp_query, esp_subscribe, and esp_upload.

Solution: Check the following:

Are you using the correct host name, port number, and login details in the command?
Is the server up and reachable? Try a ping.
Are you using -e correctly? If SSL is enabled on the server, use the utility’s -e flag. For example:
```
> esp_client -c your_user_name:your_password 
-p localhost:51011/your_workspace/your_project -e 
esp_client> loglevel 7 
esp_client> stop 
esp_client> quit 
```

If SSL is not enabled on the server, do not use -e—the connection also fails if -e is present when it should not be.

For details on command syntax, see the Utilities Guide.