# Optimizely: Email Campaign Delivery Drops — NA Region

- Impact (vendor’s label): major
- Status: resolved
- Started: 2026-06-17 14:00 UTC · Resolved: 2026-06-20 17:41 UTC · Duration: 3 d
- Updates: 7 · Affected components: Campaigns, Optimizely Data Platform - NA Region - Campaigns
- [Vendor status page: https://stspg.io/379dgcthscx7](https://stspg.io/379dgcthscx7)
- [Company: Optimizely](https://rewindex.com/company/optimizely.md)

## Summary

Optimizely reported a major degradation dropping some email campaign messages in the NA Region from 2026-06-17 14:00 UTC to 2026-06-20 17:41 UTC, lasting 3 days 3 h. Optimizely cited a likely SendGrid header-processing incompatibility and deployed a fix; it lacked records identifying which recipients received messages, complicating decisions about rerunning affected campaigns. _(machine-written, sol)_
## Timeline of updates

- **investigating** 2026-06-17 14:00 UTC: We are investigating an issue causing some email campaign messages to be dropped in the North America region. Some emails are still being delivered. Accounts using email campaigns in the region may be affected.  We will update as we learn more.
- **investigating** 2026-06-19 12:13 UTC: We are continuing to investigate this issue. We also have a support thread open with Sendgrid.
- **investigating** 2026-06-19 19:02 UTC: We are still looking into this issue and will provide updates as they become available.
- **identified** 2026-06-19 19:51 UTC: We have likely identified the root cause as a recent SendGrid change that introduced an incompatibility in header processing. We are sharing our findings with SendGrid and implementing a workaround to restore compatibility.
- **monitoring** 2026-06-19 21:50 UTC: We have deployed a fix to unblock affected customers and are actively monitoring the system to confirm stability. We are also working with our email vendor (SendGrid) to put a more complete solution in place on their side. Please note: during the period when emails were partially dropped, we do not have a record of which individual recipients successfully received messages. As a result, if you choose to re-run an affected campaign (e.g., by sending it to a new campaign), some recipients may receive duplicate emails. We will provide a further update as monitoring continues.
- **monitoring** 2026-06-19 22:29 UTC: We are continuing to monitor for any further issues.
- **resolved** 2026-06-20 17:41 UTC: This incident has been resolved.

## Rewindex changes for this incident

- 2026-06-17 14:00 UTC: [Major incident: Email Campaign Delivery Drops — NA Region](https://rewindex.com/change/ifdf943565f2644.md)


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Canonical: https://rewindex.com/company/optimizely/incidents/wxmncnqk5ph6 · Markdown: https://rewindex.com/company/optimizely/incidents/wxmncnqk5ph6.md · JSON: https://rewindex.com/api/v1/companies/optimizely/incidents/wxmncnqk5ph6 · Generated 2026-10-18T12:19:45.461Z