Sending mail in outlook fails, but telnet to SMTP server works

Yesterday, several machines at one of our locations stopped sending emails.  Outlook keeps saying "sending 1 of n" and will not successfully send.  I set up an account in Outlook Express on the server, and it is able to send just fine.  I have disabled anti-virus programs; Windows firewall is turned off;  There aren't any other add-ins that would interfere.

BUT, if I telnet into the SMTP server and manually type in the commands, I am able to send a messages - even from the machines in question.  Therefore, I know it's not an issue with the SMTP server.

Does anyone have any advice?  Thank you.
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Sounds like a routing issue;
try deleting and recreating the user's profile and see if this resolves the issue
hope this helps

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jtgerdesAuthor Commented:
ah ha.  That was the solution.  Strange how it occurred on several workstations at the same time.
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