When we build custom membership sites we often use a plugin called exec-PHP that enables us to run code inside pages and posts. It’s been a very handy tool, but it creates a message (seen only by admin level users) just above the Add New Post (or Page) window. This is what it looks like.
If you see this message, don’t worry, there is no problem. Unfortunately it cannot be removed globally. Instead the individual user must deactivate it within their profile.
Here’s a short video that demonstrates how to remove it: