I'm curious why the account is named pop.tds.net when the outgoing
(SMTP) server is smtp.gmail.com. Which 'From' address are you using,
(e-mail address removed) or (e-mail address removed)? If the latter, make sure you
have cleared it through Gmail:
Procedure to allow your custom 'From' address to be used
with Gmail:
http://mail.google.com/support/bin/answer.py?hl=en&ctx=mail&answer=22370
Also, if your incoming (POP3) server for that account is pop.tds.net, you
have a split server account which is a bit tricky to set up:
In Windows Mail go to Tools, Accounts, select that mail account, click on
Properties, Servers. Verify that the name of the outgoing (SMTP)
server is smtp.gmail.com. Make sure that the "My server requires
authentication" option is checked. Click the adjacent "Settings" button.
Select "Log on using"
then enter your (e-mail address removed) email address, and the
associated password. Click OK.
Go to the Advanced tab and verify that the port number for the
outgoing (SMTP) server is 465, and that the associated SSL option
is enabled. Do not change any receiving parameters.
Click OK. Try sending. If still no go, you may have to clear out all
the pending messages from the Outbox.