Troubleshooting Tip: Possible reasons for incoming email delivery delay

If experiencing delays in the delivery of incoming emails, this article describes possible reasons. First, examine the Cross-Search, Technical Tip: Cross-searching log messages for the delayed email. The important information is in the 'Disposition' and 'Message' columns.

1. This example shows Defer Disposition because the FortiGuard spam outbreak feature is enabled.

Technical Tip: How to view and edit spam outbreak protection period shows more information about the FortiGuard spam outbreak.

2. This example shows Defer Disposition because the FortiSandbox scan feature is enabled.

See this document: Using FortiSandbox antivirus inspection for more information.

3. This example shows deferred disposition because the FortiGuard Virus outbreak feature is enabled.

See this document: Configuring FortiGuard Antivirus service for more information.

Note:

All features described above also have their own queue where currently deferred emails are.

Here is an example for the FortiSandbox queue:

If this article does not help to understand the issue, open a ticket with TAC with the attached related Cross-Search: Technical Tip: Cross-searching log messages.