There are a number of reports from users that Microsoft Outlook won’t send mail. In most cases, they are using Outlook 2003, but Outlook 2002 is affected in some cases.

Before you can fix the problem, you need to identify the cause.

The probable causes are:

1. An add-in that marks items read if you view the Outbox.
2. Not authenticating properly with the mail server.
3. No default email account set.
4. Using a program that access the pst or ost data, such as MSN Desktop Search.
5. An antispam or antivirus scanner is scanning outgoing mail.

Troubleshooting

First, check the Send/Receive progress dialog for error codes. Browse to Tools, Send/Receive, Send/Receive settings, Show progress and click on the error tab. The error will resemble this, with a different error number and possibly a better explanation than "unknown error"

Task ‘<account> – Sending’ reported error (0×80040119) : ‘Unknown Error 0×80040119

See What does this error mean? for the reasons for some of the error codes. (If you need the text of the error code, you can select any error and use Ctrl+C to copy it.)

To fix or rule out:

Cause #1: An add-in that marks items read if you view the Outbox.

• Symptom: you look at the mail in the Outbox and it’s not bolded
• Quick Fix: Stop looking in the Outbox.
• See Outlook: After viewing the Outbox, e-mail won’t send.

Cause #2: Not authenticating properly with the mail server.

• Check your account settings.
• Tools, E-mail accounts, View or Change existing accounts. Double click on the account and click More Settings.
• Check your settings on the Outgoing server tab. Generally, enabling authentication before sending won’t cause problems.
• Do not enable SPA unless your mail server requires it.

Cause #3 No default email account set.

• Symptoms include being able to reply but not send new mail.
• This is may happen when you use a preconfigured script provided by the mail server administrator to set up your account.
• Go to Tools, E-mail accounts, View or Change existing accounts. Verify an account is set as default.

Cause #4: Using a program that access the pst or ost data.

• Symptom: Mail sends at first, then hangs in mailbox
• Send and Receive error code is: Task ‘<account> – Sending’ reported error (0×80040119) : ‘Unknown Error 0×80040119
• See http://support.microsoft.com/?kbid=814441
• Restarting Outlook (after verifying it closed completely in Task manager) may allow the mail to send. otherwise:
• Reboot and disable the problem program before starting Outlook.
• If it continues to cause problems (such as send works for awhile after restarting Outlook, then stops), uninstall the software.

Programs that have prevented mail from sending for me include the following (but are not limited to these programs):

• MSN Desktop Search
• MAPILab’s Attachment Processor
• NewsGator (v2.5 only)

If you discover other programs cause mail to hang in the Outbox, please let us know.

Cause #5: An antispam or antivirus scanner is scanning outgoing mail.

• Norton antispam plugin is one such program that will cause this problem, but it’s not the only one.
• Disable Email scanning in the software.
• Raise the timeout (Tools, Email accounts, View or change existing accounts, More Settings.)
• Check your antispam or antivirus program’s website for an update or possible workarounds.

If none of the above are the cause and the account settings look okay, turn on SMTP logging.

To turn on logging, go to Tools, Options, Other, Advanced and add a check to the box beside Enable Logging (troubleshooting). Because logging can cause Outlook to be unstable, initiate a send and receive and once you’ve reproduced the error, disable logging. Look for the log file at C:\Documents and Settings\<logon name>\Local Settings\temp\OPMLOG.LOG

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Last reviewed on Sep 12, 2011