Hi dj_trac,
There's a problem with new installations. You need to add a column named `content` of type varchar(1) to table `mail_contents`. You can add it with this SQL (assuming your table prefix is 'og_'):
ALTER TABLE `og_mail_contents` ADD COLUMN `content` varchar(1) NOT NULL default '';
We will release beta 2 soon fixing this issue and an error in time reports, along with any other bug we can fix until then.
Cheers.