See
http://www.howto-outlook.com/faq/interfaceerror.htm
--
Robert Sparnaaij [MVP-Outlook]
Coauthor, Configuring Microsoft Outlook 2003
http://www.howto-outlook.com/
Outlook FAQ, HowTo, Downloads, Add-Ins and more
http://www.msoutlook.info/
Real World Questions, Real World Answers
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"Marcelo" <(E-Mail Removed)> wrote in message
news:E7B0A6CA-25A1-43FE-BE8D-(E-Mail Removed)...
> After using Outlook 2003 for a couple of years on the same computer/cable
> internet at home, I cannot send email anymore. "The messaging interface
> has
> returned an unknown error. If the problem persists, restart Outlook" is
> the
> message I get. I restarted, even removed and re-installed outlook several
> times without success. I've had to use webmail in the meantime but am
> tired
> of it. Help?