If you find yourself in a situation where you can receive emails but cannot send them, you’re not alone. This is a common email issue caused by incorrect settings, network problems, or account restrictions. Here’s a complete guide to help you diagnose and fix the problem.
Common Reasons Why You Can’t Send Emails
Incorrect SMTP Server Settings
Outgoing emails rely on SMTP (Simple Mail Transfer Protocol) settings. Incorrect server names, ports, or authentication can block emails from being sent.
Fix:
- Double-check SMTP server name (e.g., smtp.gmail.com, smtp.outlook.com).
- Use correct ports: typically 587 (TLS) or 465 (SSL).
- Ensure authentication is enabled and your email address/password are entered correctly.
ISP Blocking SMTP Port 25
Some Internet Service Providers block Port 25 to prevent spam, which may cause outgoing email failures.
Fix:
- Use alternative SMTP ports (587 or 465) instead of Port 25.
Firewall or Antivirus Interference
Firewalls or antivirus programs may block email traffic, preventing sending.
Fix:
- Temporarily disable firewall/antivirus and try sending emails.
- Add your email client to the list of allowed programs.
Email Account Authentication Issues
Some providers require special authentication like two-factor authentication (2FA) or app passwords.
Fix:
- Ensure you are using the correct authentication method.
- Generate an app-specific password if 2FA is enabled.
Exceeded Sending Limits or Quotas
Many email services impose sending limits to prevent spam.
Fix:
- Check with your provider to see if you’ve exceeded limits.
- Wait for the limit to reset or contact support to lift restrictions.
Incorrect Email Client Configuration
Misconfigured settings in email clients (Outlook, Apple Mail, Thunderbird) can cause sending problems.
Fix:
- Remove and re-add the account.
- Double-check server settings.
Blocked or Blacklisted Sender IP Address
If your IP address is blacklisted, outgoing emails may be rejected.
Fix:
- Use a different network connection.
- Contact your ISP to check if your IP is blacklisted.
Quick Troubleshooting Checklist
| Problem | Solution |
| Incorrect SMTP settings | Verify server name, port, and authentication |
| Port 25 blocked by ISP | Use Port 587 (TLS) or Port 465 (SSL) |
| Firewall/Antivirus blocking emails | Disable temporarily or whitelist email client |
| Authentication issue | Use correct credentials or app password |
| Sending limit exceeded | Wait or contact provider support |
| Blacklisted IP | Switch network or contact ISP |
FAQs About Receiving But Not Sending Emails
Why can I receive but not send emails on my phone?
Check your SMTP settings, port numbers, and ensure authentication is enabled.
Does changing my password affect outgoing email?
Yes, you’ll need to update the password in your email client’s SMTP settings.
Can VPNs affect email sending?
Yes, some VPNs may block or interfere with SMTP traffic. Try disabling the VPN.
How do I fix Outlook not sending emails?
Go to File → Account Settings → Server Settings and verify SMTP configuration.
Is port 587 better than port 25?
Yes, Port 587 (TLS) is more secure and recommended for sending emails.
When you can receive emails but cannot send them, the issue usually lies in SMTP server settings, port restrictions, or security configurations. Following these troubleshooting steps will help you restore full email functionality and prevent future issues.
