Unable to send e-mail from outlook

[BCD]

I can receive e-mails, but not send unless Avast is shut down. Port is set at 110. Windows XP.  This just started after re- installing latest Avast Home Edition.

[Lisandro]

We will need more information to be able to help you:
- Which OS are you using? Is it up to date?
- Do you use a firewall? Which one?
- Do you have any other antivirus installed in your system?  Did you have in the past?
- Any other security programs that could interfere?
- Are you using Outlook Express or full MS Outlook?

[DavidR]

What errors are displayed when you can't send ?

You mentioned the pop3 port but didn't mention what port is used for SMTP ?

Rather than shut down avast, you can either temporarily Terminate the Internet Mail provider (if that is what you are using) or what would be preferable would be to stop outbound scanning. Internet Mail, Customize, SMTP and uncheck Scan outbound mail. That way you at least retain the protection of other inbound email scans and other avast providers.