Is there a way to turn off forwarding? I need to prevent users from forwarding emails
Are you talking about the ability to forward a single email or automatic forwarding of all incoming email?
I want to turn off the ability to forward any email from any user. Automatic or otherwise.
You could remove the forward button from the skin but that wouldn't stop someone from hitting reply removing the email address and adding another email address which would then basically be a forward.
I actually thought of that, but the biggest issue I have is people are using the filters to automatically forward messages.
Is there nothing in the configuration that would prevent any and all forwarding?
So filters aren't part of the default Roundcube package so you could disable the plugin if you don't need filters at all, otherwise you probably need to find and remove the forward rule.