==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 1.6.5
- Deployed with iRedMail Easy or the downloadable installer? installer
- Linux/BSD distribution name and version: rockylinux 8.8
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? No
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

Hello community

I have some users who complains about forwarding fail to gmail.com.

Collected those fail (resulted in bounce)

Envelop sender:
   m-4w3tij9ehyyzxqptw5739fzq7l1l4dzsdwpd21l3em5e3q2mvyirpeun@bounce.linkedin.com

Recipient: user@mydomain.com

and this account have checked "Always Forward" in Sogoweb, and forward to a @gmail.com destination.

Log
"5.7.26 To mitigate this issue, please visit Gmail's authentication guide", '5.7.26 for instructions on setting up authentication:', '5.7.26 https://support.google.com/mail/answer/ … entication hk7-20020a17090b224700b002746ab58dfcsi2055653pjb.18 - gsmtp'])

Other characteristics
* not all users experience this issues
  still verifying if those not having this issue, whether check or unchecke this option.

* even same problem account user@mydomain.com, not all mail forwards to @gmail.com fails. some do go through successful.

I am still collecting information and looking in the ARC as the gmail points to.

Will collect further information and update here.

Thanks.