SEO friendly 301 redirect .htm to .aspx

Question

I currently have a small-midsize website with .htm extensions. I have redesigned the full website, this time using a .aspx extension. I want to issue 301 redirects to keep my search engine rankings, but am unsure of how to do so from an .html page in a spider friendly way. With research I have repeatedly encountered references to ISAPI redirects (but no where can I seem to find a full explanation, just a link to isapiredirect.com, which does not load). Other than this I have been advised to run all .htm pages through the asp.net engine and issue a redirect through asp code. I have no idea how to get that done.

I am unfamiliar with asp.NET (the new site was not designed by me), and only with LAMP, which seems far more simply managed with .htaccess.

Thank you so much for any help, time, considerations or suggestions

Answer 1

You can use a .htaccess file if you get a license to the Helicon's ISAPI Rewrite module. It might be a familiar environment for you. But you are right, the home page doesn't load.

http://www.seoconsultants.com/windows/isapi/

Here's a link to some information about the product. It does work, it's a good product. I'm not sure I'd recommend ordering it while the vendor's site is down though.

EDIT

The vendor site is back up and here: http://www.helicontech.com/isapi_rewrite/