I am really new to Xoops. I am having a problem with Agenda-X. I thought my problem was something different, but it turns out this is the actual error message that I am getting.

Warning [PHP]: Cannot modify header information - headers already sent by (output started at /home/webgress/public_html/modules/system/blocks/system_blocks.php:531) in file modules/agendax/index.php line 458

It is leaving me with a blank page when I click on the link to the calendar.

Thank you ahead of time.