If you get a 404 error...
If you get the error message "The remote server returned an error: (404) Not Found. This may happen if your computer is protected by a firewall. Please make sure to put the application on the trusted programs list. - Do you want to submit the error information to our support service?", and the version of your program is below 4.9, you have to install the latest version by using the automatic updates system:
FAQ article about automatic updater
or manually download and install the latest version: