This incident has been resolved. Our team identified and corrected a configuration issue affecting Microsoft 365 email delivery through Formstack Documents. Customers should now be able to send merged documents as expected.
We apologize for the disruption and appreciate your patience.
Posted Aug 14, 2026 - 16:24 EDT
Identified
Microsoft has completed its investigation and confirmed that Exchange Online remained healthy throughout the event. The issue has been identified as a DNS-related problem affecting Proofpoint, a third-party email service used to route external email traffic.
Proofpoint has identified the root cause and is currently working to recover affected services.
Formstack Documents customers whose Microsoft 365 email traffic is routed through Proofpoint may experience failed email deliveries or DNS-related errors when sending merged documents to external recipients.
Microsoft is currently experiencing an Exchange Online service issue that may impact customers using Microsoft 365 to send email through Formstack. Customers using Microsoft 365 to send merged documents through Formstack may experience merge errors and failed email deliveries. Customers may also encounter an error when attempting to authenticate or re-authenticate their Microsoft 365 email connection. No other Documents delivery services are impacted. Microsoft is working to restore service. We will provide additional updates as they become available.
Posted Aug 14, 2026 - 09:53 EDT
This incident affected: Formstack Documents (SendGrid SMTP).