404 Error When Making A Post
I installed WPForo and everything is working properly. I can post short posts in the forums. However, when I post anything with any type of HTML such as an image or link, I get a 404 error when trying to make the post. I was having a similar issue with bbPress before moving over.
I think you have some security plugin or server firewall restriction. I'd recommend deactivate other plugins, and activate one by one in order to find the problem maker. If it doesn't help, please contact to hosting service support and let them know about this issue.
Also please leave your forum URL to allow us test it.