Does SNMPwalk for OID 126.96.36.199.4.1.13188.8.131.52.7.1 print any output at all or is listing just missing external tester ? If output is completely empty then likely SNMP configuration itself is lacking or something else blocks queries.
If just external test is missing from listing i would double check that tester entry has been properly saved to engine properties and that policy has been refreshed after configuration changes.
Thanks for your information. I will try to do ways as your recommendation
Thanks and Regards,