Will renaming a .html page to .php impact my websites google ranking?

It looks like I'm going to have change a .html file over to a .php file as I cannot parse PHP within the .html file. (I'm using IIS to handle PHP so I can't configure to parse PHP within html either)

Anyway, what I'm interested to know is if I change my .html over to .php page, how much will this impact my google ranki开发者_高级运维ngs? Will it be like starting from scratch for that particular page and is there anything I can do about this?

Yes. You need to use a "301 redirect" to maintain the rank for that page.

Watch the video here: http://www.google.com/support/webmasters/bin/answer.py?answer=93633

You can configure IIS to treat .html files as PHP files. That way you can maintain the current file without any renaming, and internally it'll be treated as PHP code. The drawback is the extra overhead of parsing all your .html files, even if only one or two will be "php-ified":

https://serverfault.com/questions/118442/how-to-treat-any-file-as-php-in-windows-iis-7

If you are worried about this, and don't want to switch to .php, you could use Ajax requests to a PHP page, through JavaScript.