How do forwarding rules cause false bounces?

Forwarding rules create complex bounce scenarios:

How forwarding works:

Message arrives at address A. Forwarding rule sends to address B. If B rejects, bounce generated. Bounce may indicate original sender issue.

False bounce scenarios:

Forward destination full: Original address looks like it bounced. Forward destination blocks you: Your reputation at B affects A. SPF failure on forward: Authentication breaks during forward.

Diagnosis challenges:

Bounce may not reveal forwarding. Original address appears problematic. Hard to identify forward chain.

Impact:

May suppress valid addresses incorrectly. Forwarding recipient's issues affect your metrics. Complex to troubleshoot.

Mitigation:

Look for forwarding indicators in bounce. Consider SRS (Sender Rewriting Scheme) impact. Accept some ambiguity in forwarding scenarios.

Forwarding bounces are blame passed along the chain. The original address may not be the problem.