Error on datafeedr plugin for wordpress

I’m new user of dreamhost hosting and I use wordpress for my installation and use also datafeedr plugin. When I want to import my datafeed script data, there is an error message:

Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

So, what’s wrong with that? Because when I tried it on my old hosting, it works. I appreciate if you don’t mind to help me for this problem. I want to build a book store with that datafeed. Thank You very much.