ISPConfig 3 - redirect url automatically adds index.html

[Chadley]

I am having a few issues when using ISPConfig 3 (nginx) and trying to redirect a website to another one "http://www.anotherdomain.com" and it automatically adds "index.html" to the end of it but not part of the redirect url. (i.e. www.anotherdomain.com/index.html). Truely "anotherdomain.com" is a php, not html. Is this something in ISPConfig 3 that I can change, or do I have to do this on the server side and edit a file?

I have tried redirect, permanent, break and last.

Thanks for your help

Chad