How do you put examples of code in articles?

[WarrenDavies]

I have written an article about how to do some stuff in HTML and PHP. So I included some example code for readers to copy and paste.

However, it won't submit, I get this error message:

Error code 15
This request was blocked by the security rules

I have tried using code tags, but this didn't work.

How can I put code into my articles?

Thanks,
Warren