Sorry for the late reply.
Looking at the error message, it's the PHP code you are running using DirectPHP that produces the error.
What is the PHP code that you're trying to run?
Please refer to the article: How to debug PHP codes in DirectPHP?
As mentioned in the article, DirectPHP uses the standard PHP function eval(). Problem is eval() does not give you any meanful debugging information. So follow the instructions in the article to copy your codes into a standalone .php file so that you can see the actual error message.
Hope this helps.