How do I change my home page from html to ASP without hurting my search engine ranking?

I did this once and my site disappeared from Google search results where once it was # 2 for certain key words. I changed it to an ASP page and bam it was gone. Funny thing was when I put it back the way it was it immediately reappeared. Needles to say I was relieved.

How do I change my home page from html to ASP without hurting my search engine ranking?
You can use a http redirect. This way, most search engine will follow to the new address (including Google) and update they cache correctly.
Reply:The problem with using ASP with variables in query strings is that the search engine crawlers don't want to touch them because they will get stuck in a loop. Best thing to do is use a url rewriting program, it will take out the ? and = and change it to / making it possible for the site to be crawled by the search engines.
Reply:It seems weird that the page disappeared after you put it into ASP. The active server pages just output an html file after talking to the server. Were all of the meta keywords and title, etc. the same both times?