- Plesk Onyx for Linux
- Horde filters like forward and auto-reply are missing in Horde Mail > Filters.
- Plesk was upgraded from 17.5 to 17.8.
This is a Plesk bug with ID #PPPM-8861 which will be fixed in the future product updates.
Reinstall/reconfigure Horde package
# yum reinstall psa-horde psa-imp psa-ingo -y
# dpkg-reconfigure psa-horde psa-imp psa-ingo
Note: It is possible to avoid the issue by enabling all filters in Horde before the upgrade.
Some Horde filters work only for Dovecot, so please check if Plesk is using Dovecot instead of Courier in Tools&Settings > Server Components.
Note: Before switching from Courier to Dovecot, this article may be interesting to check: Switch from Courier IMAP/POP3 server to Dovecot via Plesk Installer on CentOS7 removes /bin /sbin /lib /lib64 symlinks