We have many web site using SMTP to send email using Office365.. nothing have changed on office365... 2 days ago all web site can not send email...

loSMTP.cErrorMsg = "Timedout message"

Anyone know what would cause this? Could a windows update do something with .net version?

Most likely something on the office end. Several people noted they had changes with their certificates and policy changes.

Ran into something similar in that GMail recently made it all but impossible to use SMTP to send email due to policy changes - they pretty much require using their APIs nowadays. Something similar may be happening with Office 365 since MS pretty much copies just about everything Google does with search and mail.

+++ Rick ---

Thanks Rick... if Gmail is just as bad as office.. who do you use?

The big providers have always been problematic for sending SMTP emails, if you're doing anything more than one off notifications.

For anything that is semi regular I use an email provider. I use MailGun, others are SendGrid, MailChimp etc.. Most of these providers have free plans with limited usage that is usually enough for basic business scnearios. I use my free account for emails from the message, board and notifications from orders in my store and email notifications for software updates. Never run over, unless there's a problem with email hack attempts (hackers trying to hijack login or payment forms).

+++ Rick ---

I'll check one of them out.... Thanks Rick!!

I have been using SMTP2GO and it's been great. I don't know if they have a free plan, though.

Looks like they do with up to 1,000 emails/month.

The 10k plan @ $10/month looks like a fair deal, if you have consistent traffic.

I use MailGun and their free plan which is all that I need, but it looks like they've change to similar free plan pricing like SMTP2GO. Mailgun is using more and more slimey marketing and changing of terms, so I'm inclined to not recommend them anymore. I'll switch if pricing gets out of hand.

For higher volume fixed pricing SendGrid also looks good.

+++ Rick ---