Core issue
Some of the various reasons you can see these types of error messages include:
Resolution
As a workaround, complete these steps:
Problem Type
Troubleshoot software feature
Product Family
ASA Hardware & Software
Error
%PIX|ASA-1-106021: Deny protocol reverse path check from source_address to dest_address on interface interface_name
ASA Software Version
7.1
7.0
ASA Models
ASA 5500
Features & Tasks
Failover