Horde Web interface login conditions

After installing HORDE it says…

Please note: Only users with a primary e-mail address can login to the Horde web interface (with the primary e-mail address or the username).

I don’t want just anyone who has address or username to access horde…

How to change it, if i want to use my own conditions (univentionFreeAttribute for example)
or allow users in specific group only


afaik you can’t. IIRC Horde directly connects and authenticates to the IMAP server. Every user with a primary mail address gets a mailbox on the IMAP server. Giving a user a primary mail address is like ticking a checkbox that says “create mailbox, allow IMAP/SMTP logins and therefore also Horde”. For more fine-grained access rights you will need to have a look at the other groupware solutions in the Univention App Center.

Best regards,