[@robin-w Moderator 10 years, 6 months ago]

bbPress is tested with wordpress default themes. It maybe a conflict – you need to check plugins and themes

It could be a theme or plugin issue

Plugins

Deactivate all but bbpress and see if this fixes. if it does, re-enable one at a time to see which is causing the error.

Themes

If plugins don’t pinpoint the problem, as a test switch to a default theme such as twentyfifteen, and see if this fixes.