==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 4,7
- Deployed with iRedMail Easy or the downloadable installer?
- Linux/BSD distribution name and version: Centos
- Store mail accounts in which backend (LDAP/MySQL/PGSQL):  MySQL
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? YES
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====
I`ve got some errors on cron task:

mysqldump: Couldn't execute 'show events': Cannot proceed because system tables used by Event Scheduler were found damaged at server start (1577)
mysqldump: Couldn't execute 'show events': Cannot proceed because system tables used by Event Scheduler were found damaged at server start (1577)
mysqldump: Couldn't execute 'show events': Cannot proceed because system tables used by Event Scheduler were found damaged at server start (1577)
mysqldump: Couldn't execute 'show events': Cannot proceed because system tables used by Event Scheduler were found damaged at server start (1577)
mysqldump: Couldn't execute 'show events': Cannot proceed because system tables used by Event Scheduler were found damaged at server start (1577)
mysqldump: Couldn't execute 'show events': Cannot proceed because system tables used by Event Scheduler were found damaged at server start (1577) ==> Backup completed successfully.