- Level
- confirmed
- Worst impact
- Degraded
- Components
- Mailbox Provider Service Interruption
- Down Index
- 24of 100
What to do
Check whether you use SparkPost Mailbox Provider Service Interruption. Check your stack
Paste a package.json, lockfile, Terraform or a list of domains at down.guide/stack to see every provider you depend on.Confirm your retries, queues and scheduled jobs caught up after the 23h 43m it lasted.
Anything that failed between 2026-02-26 17:55 UTC and 2026-02-27 17:38 UTC may need a replay.Subscribe to SparkPost's feed to hear about the next one first. RSS feed
https://down.guide/feed?provider=sparkpost works in Slack (/feed subscribe), Discord feed bots and any RSS reader.
Updates from SparkPost 2
- monitoring
We are currently seeing elevated temporary rejection rates for email delivered to Outlook.com, Hotmail, and other Microsoft-hosted addresses. Microsoft has acknowledged the issue and is actively investigating. This is a industry-wide issue and not isolated to any specific account. We will continue to monitor and update this page as we receive more information. Next update: When Microsoft posts a resolution or Bird observes delivery rates normalizing
provider
- resolved
Microsoft has confirmed that they made additional changes the night of Thursday, Feb 26th that should have remediated most IP rate limiting and rejection issues. If you are still seeing impacts, please reach out via your normal support channels and our team can investigate and escalate with Microsoft.
provider
Reports count in aggregate; nothing about you is shown.
Corrections
None so far.
Something wrong on this page? Report an error or send us a note. Every fix is listed here.
Questions about DWN-add2569d9e
Is SparkPost still down?
No, this incident was resolved 2026-02-27 17:38 UTC. For SparkPost's live state, see https://down.guide/sparkpost.
How long did it last?
23h 43m, from 2026-02-26 17:55 UTC to 2026-02-27 17:38 UTC, by the times SparkPost posted.
What was affected?
SparkPost named Mailbox Provider Service Interruption.
What caused it?
SparkPost hasn't published a root cause. If it does, it shows here.
Where does this come from?
SparkPost's official status page, https://status.sparkpost.com, quoted verbatim. down.guide's own probes, reports and social counts are labeled as ours.