you need to post the *actual* file using the attachment option when you create a forum message. Take a copy of config.php, edit out the password and attach the whole thing. Your problem will not be in the database settings I wouldn't have thought.
Taking a guess though, did you do this
$CFG->dataroot = "home/ etc etc
if you did, it should be...
$CFG->dataroot = "/home/... etc etc
you missed the initial slash. And... is your home user *really* called /home/example, or did you edit the error message or not probably change this setting to reflect the path to your data directory? Again guessing (based on error messages) your moodledata directory would look more like...
$CFG->dataroot = "/homepages/43/d308123456/ ... etc etc
You really need to *know* these paths though!