Hotmail / Outlook Outage: Steps Marketers Should Take Now

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Image courtesy of Horia Varlan on Flickr

From yesterday 9:35 PM to 2:39 PM GMT time today, Microsoft’s email services suffered a major outage affecting a large portion of their users.

Emails sent during this period will still be delivered, but some users won’t have been able to access them until the system was working again (which it is now, according to Microsoft’s status page at

If you’re in email marketing, you can imagine the consequences of this on open and click through rates.

Here’s a list of steps to take and considerations to ensure you minimise the impact (or take advantage) of this.

So, what should you do as a marketer?

If you sent emails during this period:

  • You may want to Remail them to these users (list below) if they weren’t opened. Use the instructions and list below to create a segment that you can Remail.
  • Learn how to Remail automatically here (or just log in, it’s easy!)
  • Consider doing this when your readers won’t be drowning in all the emails they’ve been trying to access overnight.
  • ‘Remail’ is an email marketer’s superpower even in normal circumstances.
  • See here for Remail in action – in a nutshell, you can get another chunk of opens and click-throughs,as dotMailer will automatically re-send your email to non-openers after a specified time period. Simple. Superb.
  • You may want to look for open rate spikes around 9am EST to see what the impact was on your campaigns.

How to create a segment of Microsoft addresses

Just use dotMailer’s drag and drop segment creator, running a query on unopened campaigns sent during the downtime, to email addresses containing the domains listed below.

The video, right, explains how to use the tool if it’s your first time – don’t worry, you’ll love it.

The list of domains

This list covers UK and US markets. Don’t forget that other countries were affected too, so if you want to, you can run a segment including just the domain – but bear in mind that this could bring up false positives, for example, where the email address is


What about Microsoft?
Well, this is pretty bad timing for Microsoft. They’ve just migrated Hotmail to Outlook and ramped up marketing spend on it. But as this didn’t affect their entire user base, and didn’t spread quite as far as it could have (this happened overnight EST time), it’s a blip not a catastrophe for them.

In the medium term I’d be looking closely at email client trends (and we’ll be covering that here in future blogs). Gmail is growing its market share dramatically, and this has an impact on deliverability, data hygiene, and open rates.

However, frankly the amount of times my own Hotmail gets hacked – I’d say Microsoft have bigger threats to address than a very rare downtime.

Read more on TechCrunch 

Speak up

What do you think – have you seen an impact from this, or relevant trends I’d love you to share your thoughts below, or feel free to say hello on Google+

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