Category: DNS
-
What Is “mx.microsoft”?
mx.microsoft is the new MX delivery domain for Exchange Online. For years now it has been mail.protection.outlook.com, but this domain will not work with the new DNSSEC extensions that Exchange Online will start to support. When you added a new domain (called a vanity domain) to Microsoft 365, it would show you the MX record…
-
Enabling Better Mail Flow Security for Exchange Online
At Microsoft Ignite 2020, Microsoft announced support for MTA-STS, or Mail Transfer Agent Strict Transport Security. This is covered in RFC 8461 and it includes making TLS for mail flow to your domains mandatory whereas it is currently down to the decision of the sender. You can publish your SMTP endpoint and offer the STARTTLS…
-
451 4.7.0 Temporary server error. Please try again later. PRX2
There are a few articles online about this error, but none were correct for the scenario i found a clients network in. Not that I think the specifics matter, but this was Exchange Server 2016, Windows Domain Controllers running 2012 R2 and Exchange Hybrid. All the mailboxes had already moved to the cloud and the…
-
Configuring Exchange On-Premises to Use Azure Rights Management
This article is the fifth in a series of posts looking at Microsoft’s new Rights Management product set. In an earlier previous post we looked at turning on the feature in Office 365 and in this post we will look at enabling on-premises Exchange Servers to use this cloud based RMS server. This means your…
-
Is Your SenderID/SPF or DKIM Record Correctly Configured
With Microsoft having just announced that DKIM is coming to Office 365 soon (release notes here) and SenderID is already available, I thought this is a good time to write a blog on the use of DMARC to show if your records are correct. DMARC is a protocol that allows you to see the effect…
-
An “Inexpensive” Exchange Lab In Azure
This blog post centres around two scripts that can be used to quickly provision an Exchange Server lab in Azure and then to remove it again. The reason why the blog post is titled “inexpensive” is that Azure charges compute hours even if the virtual machines are shut down. Therefore to make my Exchange lab…
-
Highly Available Office 365 to On-Premises Mail Routing
This article looks at how to configure mail flow from Office 365 (via Exchange Online Protection – EOP) to your On Premises organization to ensure that it is highly available and work in disaster recovery scenarios with no impact. It is based on exactly the same principle to that which I blogged about in 2012:…
-
IPv6 Routed LAN with Windows
This blog is written to note down the steps needed to configure IPv6 on the whole of your LAN using Windows Server 2008 R2 as the router, but without installing RRAS. It also uses Hurricane Electric’s IPv6 tunnel broker service to provide the IPv6 connectivity via an IPv4 tunnel as my internet provider (Virgin Media…
-
Highly Available Geo Redundancy with Outbound Send Connectors in Exchange 2003 and Later
This is something I’ve been meaning to write down for a while. I wrote an answer for this question to LinkedIn about a week ago and I’ve just emailed a MCM Exchange consultant with this – so here we go… If you configure a Send Connector (Exchange 2007 and 2010) or Exchange 2003 SMTP Connector…
-
Domain Redirection and BPOS to Office 365 Migration
With Microsoft Exchange Online via BPOS (the precursor to Office 365) you were able to configure a simple CNAME redirection to make access to OWA easier for your users. For example, you could create a CNAME in DNS for mail.fabrikam.com (where fabrikam.com is your domain in BPOS) which pointed to go.domains.live.com and then when users…