==== Required information ====
- iRedMail version (check /etc/iredmail-release): v0.9.5-1
- Linux/BSD distribution name and version: ubuntu 16.04.01
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): Apache
- Manage mail accounts with iRedAdmin-Pro? no
- Related log if you're reporting an issue:
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i feel my mail server sent mail slow
I'd skip the virus check some file formats
example: file.zip, file.rar........ : normail scan
                file.xls, file.xlsx, file.doc : not scan