Horde webmail does not work on the domain after upgrading Parallels Plesk Panel to version 10.
The Horde webmail option is not available in the mail server settings and it is not possible to set it for the domain.
However, the "psa-horde" component is installed on the server.
# rpm -qa psa-horde
Horde Webmail was not registered in Plesk after the upgrade. It is necessary to register Horde webmail in Plesk using the webmailmng utility. This utility can be found in the directory PRODUCT_ROOT_D/admin/bin/.
# /usr/local/psa/admin/bin/webmailmng --install --name=horde
# /usr/local/psa/admin/bin/webmailmng --enable --name=horde
With these commands, Horde webmail will be registered in Plesk and it will be possible to enable it on the domains.