==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 1.1
- Deployed with iRedMail Easy or the downloadable installer?  downloadable installer
- Linux/BSD distribution name and version: Centos 7.6
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): LDAP
- Web server (Apache or Nginx): Apache
- Manage mail accounts with iRedAdmin-Pro? No
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

Good day, fellas!
I set up email login instead of samaccountname. My AD looks like corp.example.local. My IREDMAIL centos 7 server looks like mail.corp.example.local. Attributes of user2: userprincipalname set to 1111@corp.example.local, samaccountname set to 1111, mail set to user2@example.local. Attributes of user1 are similar: userprincipalname set to 2222@corp.example.local, samaccountname set to 2222, mail set to user1@example.local. I did not configure AD example.local.
I can send email to user2@example.local. But user2 does not see it in the inbox. I tested it with Mozilla thunderbird, Chrome.
Can you help me to understand maillog and how to configure it correctly
Feb 17 13:40:13 postfix roundcube: <eo9gtkd4> PHP Error: LDAP: Bind failed for dn=mail=user2@example.local,ou=Users,domainName=example.local        ,o=domains,dc=corp,dc=example,dc=local. Invalid credentials (GET /mail/?_task=addressbook&_action=photo&_email=user2%40example.local&_error=1        )