1. Check if there is an error message presented to you after pressing ‘Send’.
2. If an error message is present, carefully read it and check if any changes are necessary.
3. Check the address and subject fields for typing errors.
4. Make sure your outgoing server port and settings are correct.
5. Try to manually configure the Outgoing Server (SMTP) settings.
6. Contact your internet service provider if the issue persists.