Understanding the Email Flow That Powers Email-to-Case Processing
Before troubleshooting, understand how Email-to-Case processes emails:
- Customer sends email to support@yourcompany.com
- Your email system forwards to the Salesforce routing address
- Salesforce receives and processes the email
- Case created with email content, attachments, and sender info
- Assignment rules route the case to the appropriate queue/agent
- Auto-response sent to customer (if configured)
Issues can occur at any point in this flow. Identifying where the breakdown occurs is key to resolution.
Issue: Cases Not Creating When Customers Send Emails to Your Support Address
When emails don’t create cases, check these areas:
Email Forwarding May Have Stopped or Been Misconfigured:
Verify forwarding is active in your email system. Send a test email and check if it reaches the Salesforce routing address.
Routing Address May Be Inactive or Contain Configuration Errors:
Confirm the routing address is active in Salesforce Email-to-Case settings. Check for typos in forwarding configuration.
Email Size May Exceed the 25 MB Processing Limit:
On-Demand Email-to-Case has a 25 MB limit. Emails exceeding this fail silently. Check original email size.
Spam Filtering May Intercept Emails Before They Reach Salesforce:
Your email system may be filtering emails before forwarding. Check spam/junk folders and filtering rules.
Salesforce Daily Limits May Have Been Reached:
According to Salesforce Email-to-Case limits documentation, there are daily limits on case creation. Check if limits have been reached.
Direct Send Test Isolates Whether Forwarding or Salesforce Is the Problem:
Send an email directly to Salesforce's routing address (bypassing your forwarding) to isolate whether the issue is with forwarding or Salesforce.
Issue: Duplicate Cases Created When Customers Reply to Existing Case Emails
When email replies create new cases instead of adding to existing cases, the threading configuration needs attention. As described in the Salesforce Email-to-Case Threading documentation:
Thread ID Missing from Outbound Case Emails:
Verify Thread ID is included in outbound case emails. Check Email-to-Case threading settings.
Subject Line Changes Break Thread Matching:
If customers modify subject lines, threading may fail. The thread ID in the body is more reliable than the subject.
Email Client Software Strips Thread Identifiers:
Some email clients remove the Thread ID. Test with different email clients to identify problematic ones.
Threading Feature Not Enabled in Email-to-Case Settings:
Confirm threading is enabled in Email-to-Case settings. Check the Thread ID pattern configuration.
Replies to Closed Cases May Generate New Records:
Replies to closed cases may create new cases depending on settings. Configure closed case reply handling.
Issue: Cases Routing to the Wrong Queue or Being Assigned to Incorrect Agents
When cases route to incorrect queues or agents:
Rule Evaluation Order Determines Which Criteria Match First:
Assignment rules evaluate in order—first match wins. Review rule entry order in Setup → Case Assignment Rules.
Case Data May Not Match the Expected Rule Criteria:
Case data may not match rule criteria. Check case field values against rule conditions.
Default Owner Catches Cases When No Assignment Rules Match:
If no rules match, cases go to the default owner set in the routing address. Verify the default is correct.
Assignment Rule May Not Be Active in the Current Configuration:
Confirm the assignment rule is active. Only one assignment rule can be active at a time.
Multiple Routing Addresses May Have Different Default Settings:
Different routing addresses may have different default settings. Verify correct forwarding to the correct routing address.
Issue: Email Attachments Not Appearing on the Created Case Records
When email attachments don’t appear on cases, review these potential causes. As noted in the Email-to-Case Threading Limitations documentation, several constraints affect how attachments are processed:
Individual Attachment Size Exceeds Salesforce Limits:
Individual attachments over the limit are dropped. Check attachment sizes against Salesforce limits.
Blocked File Types Prevent Certain Attachments from Saving:
Some file types may be blocked. Review Salesforce file type restrictions.
Combined Email and Attachment Size Exceeds 25 MB Threshold:
Combined email + attachments exceeding 25 MB causes the entire email to fail.
Email Forwarding System Strips Attachments During Transit:
Some email systems strip attachments during forwarding. Test attachment forwarding separately.
Organization Storage Limits Prevent New Files from Being Saved:
Salesforce file storage limits may prevent attachment saving. Check org storage usage.
Issue: Auto-Response Emails Not Reaching Customers After Case Creation
When customers don’t receive auto-response emails:
Auto-Response Rule May Not Be Active:
Confirm auto-response rule is active in Setup → Case Auto-Response Rules.
Case Properties May Not Match Auto-Response Rule Criteria:
The case may not match the auto-response rule criteria. Review rule conditions against case values.
Email Template May Be Inactive or Contain Errors:
The email template may be inactive or have errors. Test template separately.
Daily Email Sending Limits May Have Been Exhausted:
Auto-responses count against Salesforce email limits. Check if the daily limit is reached.
Deliverability Issues May Send Auto-Responses to Spam:
Auto-response may be sent, but landing in spam. Check email deliverability settings and sender reputation.
Issue: Cases Not Linking to Existing Contact Records in Salesforce
When cases don’t link to existing Contacts, use the Salesforce custom thread ID documentation to verify your matching configuration:
Sender Email Address Does Not Match Any Contact Record:
Sender email doesn’t match any Contact email field. Check for typos or alternate email addresses.
Multiple Contacts Share the Same Email Address:
If multiple Contacts have the same email, linking may fail or pick the wrong Contact. Clean up duplicate emails.
Auto-Contact Creation Is Disabled for Unknown Senders:
If auto-Contact creation is disabled, cases from unknown senders won’t have a Contact. Enable or manually create Contacts.
Custom Email Fields Are Not Checked During Matching:
Email-to-Case checks the standard Email field. Custom email fields aren’t matched automatically.
Issue: HTML Email Content Displaying Incorrectly on Case Records
When email content displays incorrectly on cases:
HTML Email Acceptance May Not Be Enabled:
Verify ‘Accept HTML Email’ is enabled in routing address settings.
Complex HTML Layouts May Not Render Perfectly:
Highly formatted emails may not render perfectly. This is expected behavior for complex layouts.
Inline Images May Be Blocked When Hosted Externally:
Inline images may not display if hosted externally and blocked. Images as attachments work better.
Systematic Diagnostic Steps for Isolating Email-to-Case Failures
Follow this systematic approach to troubleshooting. As documented in the Trailhead Support Case Management project, effective case management depends on proper configuration at every stage:
Step 1: Check Email System Logs for Delivery Confirmation
Check email system logs—was email sent to Salesforce routing address?
Step 2: Review Salesforce Email Logs for Processing Records
Review Salesforce email logs (Setup → Email Log Files)—did Salesforce receive email?
Step 3: Check Email-to-Case Error Notifications for Processing Failures
Check Email-to-Case error notifications—any processing errors?
Step 4: Test Direct to Routing Address to Isolate the Failure Point
Test direct to routing address—isolate forwarding vs. Salesforce issues.
Step 5: Review Recent Configuration Changes That May Have Introduced Issues
Review recent configuration changes—did something change?
Proactive Measures for Preventing Future Email-to-Case Problems
Proactive measures to avoid Email-to-Case problems:
Monitor Case Creation Volume Regularly with Dashboards:
Set up dashboards tracking case creation volume. Sudden drops indicate problems.
Test Email-to-Case After Every Configuration Change:
Always test Email-to-Case after any email system or Salesforce configuration changes.
Document All Configuration Settings for Troubleshooting Reference:
Maintain documentation of all Email-to-Case settings for troubleshooting reference.
Configure Error Notifications to Catch Routing Failures Quickly:
Configure email notifications for routing failures to catch issues quickly.
How Email-to-Case Troubleshooting Reveals Marketing Email Interactions
Troubleshooting may reveal marketing email interactions:
Campaign Replies May Create Unexpected Support Cases:
Replies to email campaigns may create cases. Configure routing for marketing responses.
Sequence and Drip Campaign Responses Generate Support Inquiries:
Email sequences and drip campaigns may generate support inquiries captured by Email-to-Case.
Unsubscribe Requests Create Cases That Require Prompt Processing:
Unsubscribe requests via reply create cases. Honor opt-out preferences promptly.
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Key Takeaways
- Understand the email flow to identify where breakdowns occur
- Cases not created usually stem from forwarding, size limits, or routing address issues
- Duplicate cases result from threading configuration problems
- Systematic diagnosis using email logs isolates issues faster
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