%plesk_bin%\mchk.exe command do?
mchk utility does the following:
Restores domain configuration in Mailenable
Restores mail accounts with their passwords and limits
Restores mail lists settings
In other words if you delete mail account in MailEnable, it will be possible to restore domain/mail configurations running mchk command (but content will not be restored).
For more information please refer to documentation at:
Warning: all the data created not through Plesk (mail accounts, domains) will be removed!
In addition, the following data will be removed if it is created directly in mail server:
- calendar appointments
- RSS feeds settings
- auto-responder settings
- maillists settings