We have had some reports of problems routing to Offic365. We have tried re-routing the traffic via various routes and traffic still fails deep within the Microsoft network. We are trying to contact Microsoft regarding this. This may affect sending of email to Office365/Outlook/Microsft/Hotmail/etc accounts as well as general access of Office 365 services.
The problem we're seeing is certain *.protection.outlook.com mail servers not accepting connections on port 25 from us when we try send email to them. Luckily the hosts for microsoft-com.mail.protection.outlook.com do work, and we have emailed Microsoft regarding this.
We have not yet heard back from Microsoft, but we encourage Office 365 customers to report this as a fault to Microsft too. The problem can be seen by attempting connections to the mail servers listed as the MX records for your domain, this will be in the form of *.mail.protection.outlook.com. This can be seen doing:
telnet DOMAIN.mail.protection.outlook.com 25
Where 'DOMAIN' is your domain name with .'s turned in to -'s.If it fails, it will timeout, with a message such as:
Unable to connect to remote host: Connection timed outIf it works, then the message is similar to:
220 BL2NAM06FT009.mail.protection.outlook.com Microsoft ESMTP MAIL Service ready
Separate to our emails to the Microsoft NOC we've had a 40 minute call with the Office356 enduser helpdesk, and they are investigating further.
It seems Office365 servers in Dublin are the ones which are not accepting connections from us. These look to have IP addresses starting 213.199.154.x. Where as Office365 servers in the US such as 104.47.46.x and possibly 23.103.156.x are accepting connections from us OK.
We have been pursuing various channels to speak to staff at Microsoft who are in a position to be able to help - so far it's proving difficult.
We have been talking to the general Office365 technical support team and team leaders, who after a couple of hours are starting to realise that the problem is one which they can't help with, and are attempting to move the ticket over to a network team.
Routing is now working again, we believe the problem is due to to routing through one of our routers which we have disabled this evening. We are still investigating the actual root cause of this. We would like to thank the other customers who reported this fault to the Office365 help desk, and do apologise for the frustration and inconvenience this has caused.