Outlook junk folder
Outlook.com / Microsoft 365 recipients see mail in Junk or experience SNDS/blocking symptoms.
Problem summary
Outlook.com / Microsoft 365 recipients see mail in Junk or experience SNDS/blocking symptoms.
Symptoms
- Messages land in Junk for Outlook/Hotmail/Live addresses
- SNDS shows elevated filter or complaint activity
- Throttling or rejections accompany junk placement
Possible causes
- IP/domain reputation issues visible in SNDS
- Complaint or trap activity
- Authentication or identity inconsistencies
- Content/URL patterns Microsoft treats as bulk risk
How to diagnose
- Review SNDS data for the sending IPs
- Confirm SPF/DKIM/DMARC alignment on Microsoft samples
- Segment junk outcomes by campaign and IP
How to fix
- Remediate listed IPs and pause aggressive sends
- Align authentication and stabilize From identity
- Improve list quality and suppress complainers
How to verify
- SNDS filter rates improve
- Junk placement declines for Outlook cohorts
Prevention
- Enroll and monitor SNDS continuously
- Keep complaint rates low with clear consent
When to escalate
- Production mail is failing for a material share of recipients after remediation attempts