======== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 0.9.8 MARIADB edition
- Linux/BSD distribution name and version: CentOS 7.5.1804
- 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.
====

Hi, I'm testing iRedMail related functions and meet some problems below:

1.Outlook 2016 can't sync mail read status from mobile phone (iOS & Android)
When I changed mail read status on mobile phone, Outlook 2016 won't update the mail read status in the meantime, but it will on Roundcube and SOGo webmail, and it work normally on Outlook 2013.

2.Global address book sync problem
When I add a Exchange account on iOS, it will auto sync calendar and private contacts from SOGo, how to sync public contacts on iOS from SOGo too?
When I add a Exchange account on Android, it will auto sync calendar and private contacts too, but when I use "CardDAV-Sync free" APP to sync public contacts, it only sync normally at first time and will failed afterwards, why?

Related software version：
Office 2016 Home and Business Version 1807 (32 & 64 bit)
iOS 11.4.1
Android 7.0