IronPort - advanced configuration guide

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else {insert-header("X-ExtLoopCount3", "from $RemoteIP");}}
else {insert-header("X-ExtLoopCount2", "from $RemoteIP");}}
else {insert-header("X-ExtLoop1", "1"); }
Cisco IronPort AsyncOS 7.6 for Email Advanced Configuration Guide
Chapter 6 Using Message Filters to Enforce Email Policies
Note By default, AsyncOS automatically detects mail loops and will drop messages after 100 loops.
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