Understanding Results

This guide explains how to interpret InboxIssue test results and what actions to take.

Delivery Status

Each test result shows where your email was delivered:

Status	Icon	Meaning
Inbox	✅	Email delivered to primary inbox
Spam	⚠️	Email delivered to spam/junk folder
Missing	❌	Email not received within 60 minutes

What "Missing" Means

A missing result can indicate:

Email was blocked at the server level
Email bounced before delivery
Significant delivery delay (over 60 minutes)
Sending issue (email never sent)

Authentication Results

InboxIssue analyzes email authentication headers:

SPF (Sender Policy Framework)

Verifies that the sending server is authorized to send email for your domain.

Result	Meaning
pass	Sending IP is authorized
fail	Sending IP is NOT authorized
softfail	Sending IP is probably not authorized
neutral	No SPF policy or inconclusive
none	No SPF record found

DKIM (DomainKeys Identified Mail)

Verifies that the email content hasn't been modified in transit.

Result	Meaning
pass	Signature verified successfully
fail	Signature invalid or missing
none	No DKIM signature present

DMARC (Domain-based Message Authentication)

Policy that tells receivers what to do with unauthenticated emails.

Result	Meaning
pass	Email passes DMARC alignment
fail	Email fails DMARC checks
none	No DMARC policy found

For best deliverability, aim for pass on all three: SPF, DKIM, and DMARC.

Microsoft Spam Scores

For Microsoft-hosted mailboxes (Outlook.com, Office 365), InboxIssue extracts detailed spam analysis.

SCL (Spam Confidence Level)

Score	Interpretation	Action
-1	Bypassed filtering	Safe sender/allowlist
0-1	Very low spam probability	Delivered to inbox
2-4	Low spam probability	Usually delivered to inbox
5-6	Medium spam probability	May go to spam
7-8	High spam probability	Likely spam folder
9	Very high spam probability	Almost certainly spam

BCL (Bulk Complaint Level)

Measures if your email looks like bulk/marketing mail.

Score	Interpretation
0	Not bulk mail
1-3	Low bulk characteristics
4-7	Medium bulk characteristics
8-9	High bulk characteristics

Even legitimate marketing emails may have a BCL of 3-5. Focus on keeping SCL low.

Composite Authentication (CompAuth)

Microsoft's combined authentication result.

Code Range	Meaning
0	Explicit auth failure (DMARC reject)
1	Implicit auth failure
100-199	Authentication passed
200-299	Soft-passed implicit auth
300-399	Not checked
400-499	Bypassed checking

Common Issues and Fixes

High Spam Rate

Symptoms: Most emails landing in spam

Common Causes:

Failed authentication - Fix SPF, DKIM, DMARC
Poor IP reputation - Check blacklists, warm up new IPs
Content issues - Avoid spam trigger words
Missing unsubscribe - Add List-Unsubscribe header

Missing Emails

Symptoms: Emails not received at all

Common Causes:

IP blocked - Check major blacklists (Spamhaus, Barracuda)
Bounce - Check your mail server logs
Rate limiting - Sending too fast
Content filtering - Attachment or link issues

Inconsistent Results

Symptoms: Same email, different results across providers

This is normal! Different providers have different:

Spam filtering algorithms
Reputation databases
Content analysis rules

Improving Deliverability

Quick Wins

Set up authentication
- SPF record for your domain
- DKIM signing enabled
- DMARC policy published
Check sender reputation
- Google Postmaster Tools
- Microsoft SNDS
- Blacklist lookups
Review content
- Avoid ALL CAPS
- Balance text and images
- Include plain text version

Long-term Strategy

Maintain list hygiene - Remove bounces and unengaged
Warm up new IPs - Gradually increase volume
Test regularly - Run tests before major campaigns
Engage subscribers - Good engagement improves reputation

Next Steps

Test Case Examples - Real-world scenarios
Deliverability Insights - Deep analysis
Webhooks - Automated alerts

Understanding Results

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