dstiles - 8:40 pm on Jul 6, 2009 (gmt 0)

You can automatically 301 (eg) .html pages to .asp using at worst the 404 interceptor (ie create a new script and assign it in place of the default 404 handler). Check for .html and substitute .asp, check if the file exists - it may not - and issue a 301 (page exists elsewhere) or 404 (not found).

It's quite reasonable to create a new page title, meta description etc automatically (I include these options as fields in my page-source database).

You MAY lose ranking. But then, google drops ranking and SERPs all the time for no reason at all that anyone can discern - read WebmasterWorld!

One thing I very strongly advise NOT doing: a customer of mine, against my advice, gave his new pages differnt names, so there was no correspondence between old and new. It was impossible to auto-redirect at all, even if the page content was the same (which mostly it wasn't). As far as I know his site still hasn't recovered 18 months later. Some people don't listen. :(

A better solution may be to use an Apache server that allows you to rename the file extensions on the fly. Alternatively, if you have control over your server you can specify that .html (whatever) is really ASP and should be parsed as such. IIS servers aren't particularly clever but that switch is possible.