Sending gmail from Outlook

[Clippy]

Who is your ISP?

For example, I recently switched to O2 and when configuring my Outlook client to use with my Yahoo account, I had exactly the same issue.

I called O2 support who advised me that I had to amend the smtp server address to one of their servers as it acted as, I believe, a relay.

Perhaps your ISP had implemented something similar?
(Although, I would have thought, if they had, they would advise you beforehand).

[d000hg]

I've been using Outlook to access my gmail for over a year, through IMAP. Suddenly, sending emails has started failing, though receiving still works - the mails just sit in my Outbox and I get unhelpful "send failed" errors:

Task 'XXXXXXXX@googlemail.com - Sending' reported error (0x80042109) : 'Outlook cannot connect to your outgoing (SMTP) e-mail server. If you continue to receive this message, contact your server administrator or Internet service provider (ISP).'

I've noticed gmail/IMAP can be a bit flaky, is this just something that happens or do I need to do anything to fix it on my end?

edit: I have 2 gmail accounts configured through Outlook and neither is working. A different mailbox I also have set up from my web-host IS working though. Perhaps a gmail mailserver is playing up, but it's been over 12 hours now which is quite a long outage if so...