How to respond to email delivery outages at ISPs like Orange?
Matthew Whittaker
Co-founder & CTO, Suped
Published 27 Apr 2025
Updated 19 Aug 2025
6 min read
Email delivery outages at Internet Service Providers (ISPs) like Orange can be a significant headache for any business relying on email communication. These disruptions, whether planned maintenance or unexpected failures, directly impact your ability to reach subscribers and can damage your sender reputation. While you can't prevent an ISP from experiencing issues, you can control how you respond to minimize the fallout.
Understanding how to quickly detect, react, and recover from such outages is crucial for maintaining strong email deliverability. This involves proactive monitoring, clear communication, and strategic adjustments to your sending practices. Failing to adapt during an outage can lead to prolonged delivery problems, increased bounce rates, and potential blacklisting or blocklisting of your sending IP addresses or domains.
Identifying an outage
The first step in responding to an email delivery outage is recognizing that it's happening. Often, early indicators appear in your email logs before official announcements are made. Keep a close watch on your bounce rates, deferred messages, and any unusual spikes in delivery times specifically for the affected ISP, such as Orange.fr. Look for common error codes like 4XX (temporary failures) or OFR_999errors specific to Orange. These can signal that the receiving server is overwhelmed or experiencing issues.
Beyond your internal metrics, external sources can provide valuable real-time information. Community forums and social media, for instance, are often buzzing with user complaints even before an ISP acknowledges a problem. Websites like Downdetector can offer a quick visual of reported outages for various services, including email. Always cross-reference multiple sources to confirm the scope of the outage and ensure it's not an isolated issue specific to your sending infrastructure.
Signs of an outage
Increased deferrals: A sudden rise in deferred emails to Orange, especially with 4XX SMTP codes.
Slow connections: Very long connection times or timeouts when attempting to deliver mail.
Bounce spikes: An unexpected surge in hard or soft bounces specifically from Orange domains.
Once an outage is confirmed, the immediate priority is to pause your email queues to the affected ISP. Sending emails into a black hole or against an overloaded server will not only fail to deliver your messages but can also actively harm your sender reputation. ISPs interpret continued attempts to deliver during an outage as aggressive sending behavior, which can lead to your IPs or domains being blacklisted even after the outage is resolved.
Internally, communicate the outage to all relevant teams, including customer support, marketing, and sales. They need to be aware of potential delays or non-delivery to manage customer expectations. Prepare internal messages for your support staff so they can effectively answer customer queries about delayed or missing emails. This proactive communication prevents frustration and maintains trust, especially if your customers are experiencing issues with their Orange.fr accounts.
Before an outage: Proactive measures
Robust monitoring: Implement systems to track delivery metrics, bounce rates, and deferred queues in real-time.
ISP contact lists: Keep an updated list of postmaster contacts and outage reporting channels for major ISPs.
Pause queues: Immediately halt sending to affected domains to prevent reputation damage.
Internal alerts: Notify relevant internal teams about the outage and its impact.
External communication: If necessary, inform customers about email delays, leveraging alternative communication channels. Clarity is key.
Communicating with the ISP
Direct communication with the affected ISP's postmaster team is vital. Most large ISPs, including Orange, maintain a postmaster site or specific contact channels for senders. Orange.fr recently launched a new site, where they share guidelines and updates. If you have an established relationship, reach out through your dedicated contact. Otherwise, use their public channels. The goal is to get confirmation of the outage, understand its nature, and get an estimated time to resolution.
When contacting them, be prepared to provide specific details about the issues you're observing. This includes timeframes, error messages (like SMTP greeting failed or delivery time expired), and any other relevant logs that illustrate the problem. It helps them diagnose the issue faster and confirms that your email practices are not contributing to the problem. Be patient, as these teams are often overwhelmed during a widespread outage.
Even during an outage, an ISP (like Orange) still evaluates sender legitimacy. Ensure your email authentication records (SPF, DKIM, DMARC) are correctly configured. Orange's guidelines emphasize that your sender's domain must be linked to a website with a legal notice for transparency. These foundational elements of good sending practice are always important, but especially so when an ISP is under stress.
Information to provide
Why it's important
Your sending IP addresses
Helps the ISP identify your traffic and correlate it with their internal logs related to the outage.
Clarifies which specific recipient domains are experiencing issues from your end.
Timestamps of observed issues
Provides a timeline for their investigation, matching your observations with their incident reports.
Specific error messages/SMTP codes
Crucial for diagnostics, as they indicate the nature of the rejection or deferral.
Volume of affected emails
Helps the ISP understand the scale of the impact on your sending.
Mitigating impact and resuming sending
Once an ISP confirms the outage is resolving, the key is to gradually resume sending. Do not immediately open the floodgates. Ramping up your email volume slowly allows the ISP's systems to normalize and helps you avoid triggering any post-outage throttling or new blocklists (or blacklists). Monitor your queue activity closely during this phase. Look for connection increases, successful deliveries, and a reduction in deferrals or errors. For example, if you see connection counts jump from 1 to 168, as observed by an expert during an Orange outage, it's a good sign that things are improving.
After the outage, conduct a thorough review of your delivery logs. Analyze the bounce codes and error messages received during and immediately after the outage. This data is invaluable for understanding how your email infrastructure performed under stress and identifying any lingering issues. Pay particular attention to persistent deferrals or new bounce codes that suggest ongoing problems specific to Orange or other ISPs like Yahoo or Spectrum. If Orange was throttling your emails, this review can highlight if the throttling behavior has changed.
Finally, assess and update your emergency response plan. Every outage provides valuable lessons. Document what worked well, what didn't, and what improvements can be made. This includes refining your monitoring alerts, improving communication protocols, and establishing fallback strategies. Having a robust plan in place will ensure you're even better prepared for the next unforeseen event, minimizing both downtime and reputation risk.
Best practices for recovery
Gradual resumption: Increase sending volume slowly to the affected ISP after the outage is declared resolved.
Log analysis: Review your email logs for new bounce codes or persistent deferrals post-outage.
Always have real-time monitoring of your email queues and delivery rates for all major ISPs, including Orange, to detect anomalies quickly.
Establish clear internal communication channels so all teams are aware of an outage's status and its impact on email delivery.
Maintain a direct line of communication with ISP postmaster teams; they are your best source for official updates during incidents.
Common pitfalls
Continuing to send mail at full throttle into an outage, which can severely damage your sender reputation and lead to blacklisting.
Failing to communicate internally, leaving customer support and other teams unprepared for customer inquiries about delayed emails.
Ignoring post-outage monitoring and not adjusting sending strategies, potentially prolonging deliverability issues.
Expert tips
Implement automated queue pausing for specific domains if a high rate of deferrals or specific error codes are detected.
Leverage DMARC reports to analyze delivery outcomes during and after outages, providing granular insight into affected traffic.
Periodically review and update your incident response plan to incorporate lessons learned from each outage, refining detection, communication, and recovery steps.
Expert view
Expert from Email Geeks says: If you can pause your queues during an incident at an ISP like Orange, please do so, as you shouldn't actually be delivering anything anyway.
2019-04-25 - Email Geeks
Marketer view
Marketer from Email Geeks says: Even during a reported outage, it appears that some messages are still being delivered to Orange, so it's important to monitor closely.
2019-04-25 - Email Geeks
Navigating ISP email outages
Responding effectively to email delivery outages at ISPs like Orange requires a combination of vigilance, quick action, and strategic communication. By proactively monitoring your delivery metrics, pausing sending during confirmed incidents, communicating transparently with both your internal teams and the ISP, and carefully resuming operations, you can mitigate the impact of outages. Continuous learning and refinement of your response plan are key to maintaining high deliverability rates and protecting your sender reputation in the long run.
Orange can be a significant headache for any business relying on email communication. These disruptions, whether planned maintenance or unexpected failures, directly impact your ability to reach subscribers and can damage your sender reputation. While you can't prevent an ISP from experiencing issues, you can control how you respond to minimize the fallout.
Orange.fr accounts.
Orange.fr, Wanadoo.fr)
