Ah, so you get the message when you render, not when you load the shader. That's not what you said. :O)

Sorry, I don't know what could cause that. You might still check the File Search preference setting, just to be sure.

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)