Not able to send emails from my optunet account on outlook

Question

Hello there,

I have just recently downloaded all my emails onto Outlook however, both my optusnet accounts will not send through outlook.

I receive them but I cannot send from them.

Can someone please help me?

Answer 1

Hi Joanna Papoulis,

Welcome to the Microsoft Q&A forum.

I understand how frustrating this can be, especially when you can receive emails but are unable to send any messages from your Optusnet account in Classic Outlook for Windows.

I also noticed that there is a Q&A Assist response in the thread. The troubleshooting steps provided there are generally appropriate for Classic Outlook scenarios like this. If you have had a chance to review and try those steps, please let me know how it went. I would like to add a bit more context without repeating the same points.

Since this issue only affects sending and the account is a third‑party Optusnet email account, one common area to double‑check is the outgoing server (SMTP) requirements enforced by the email provider. In many cases, receiving works while sending fails if Outlook is not fully aligned with the provider’s SMTP authentication or encryption requirements.

Here are a few additional points that may help, focusing specifically on Optusnet-style ISP accounts:

1. In Account Settings > Change > More Settings > Outgoing Server, make sure “My outgoing server (SMTP) requires authentication” is enabled, and that it is set to use the same settings as the incoming mail server.
2. Verify that the SMTP port number and encryption method match the current requirements from Optusnet. Some providers require a specific port (for example, 465 or 587) and SSL or TLS for sending.
3. If the Optusnet account password was changed recently through the provider’s website, Outlook may still be using the old credentials for sending. Re‑entering the password in Outlook can help ensure it is updated for the outgoing server as well.
4. If possible, signing in to the Optusnet webmail interface and sending a test email from there can confirm whether sending is allowed on the provider side and help rule out an account-level restriction.

As a reminder, contributors on this forum do not have access to email provider systems or Outlook backend services, so guidance here is limited to client-side configuration and general best practices.

Please feel free to let me know whether you were able to try the Q&A Assist steps and the additional checks above, and what the results were, so we can narrow this down further.

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Answer 2

Try these steps in classic Outlook, in order:

1. Confirm Outlook is online

• Look at the bottom status bar. If it shows Disconnected, Working Offline, or Trying to connect…, Outlook cannot reach the mail server.
• Go to Send/Receive tab → Work Offline to toggle it off (it should not be highlighted).
• Then click Send/Receive and try sending again.

2. Check Internet connectivity

• Open a browser (Microsoft Edge or Chrome).
• Browse to http://www.microsoft.com or http://www.bing.com.
• If these do not load, fix the network issue first (see Fix network connection issues in Windows). Outlook will not send mail without a working connection.

3. Check for large/stuck messages

• In Outlook, open the Outbox folder.
• If there are messages stuck there, especially with large attachments (over ~20 MB), open the oldest one first.
• Remove or reduce large attachments, or replace them with a link (see Reduce attachment size to send large files with Outlook).
• Send the message again and then try sending a new test email.

4. Verify password and account settings If the password for the Optusnet account was changed on the provider’s website, it must also be updated in Outlook:

• Go to File → Account Settings → Account Settings… → E-mail tab.
• Select the Optusnet account → Change and confirm the username, password, and server settings are correct per Optusnet’s instructions.
• Use Test Account Settings in that dialog to confirm Outlook can send.

5. Check antivirus email scanning

• Some antivirus products block outgoing mail when they detect issues.
• Temporarily disable email scanning in the antivirus (or consult the antivirus help desk) and test sending again.

6. Repair the Outlook profile If only these Optusnet accounts are affected and settings are correct, the profile may be damaged:

• Follow Fix your Outlook email connection by repairing your profile to repair the existing profile.
• If that does not help, create a new Outlook profile and re-add the Optusnet accounts, then test sending.

7. Start Outlook in safe mode Add-ins can block sending:

• Press the Windows key, type outlook.exe /safe, press Enter.
• In safe mode, send a test email from the Optusnet account.
  • If it works in safe mode, disable problematic add-ins or continue using a fresh profile (see Create an Outlook profile).

8. Repair Outlook installation and data file If sending still fails:

• Run an Office repair as described in Repair an Office application.
• If the Optusnet account uses a .pst file, run the Inbox Repair Tool as in Repair Outlook data files (.pst and .ost) and then test sending again.

If an error code such as 0x80042109, 0x800ccc0e, or similar appears when sending, the same troubleshooting steps above (connectivity, account settings, antivirus, profile repair, and data file repair) are the recommended resolution path.

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References:

• I can't send or receive messages in Outlook
• Can't send or receive email in Outlook.com