In our CMS I have a custom URL rewriting module that creates SEO friendly URLS based on the users page name. This was great and worked well, but I have noticed over the past couple of years that even though Google say they treat .aspx, .php extensions the same as static .htm pages - .htm pages just seem to do better in the SERPS for the sites I have managed. [more]
So I went about trying to find out a way of auto changing the extension to .aspx to .htm, well after a while I realised I was being a plank – The easiest and quickest way to go about it was to use the fantastic ISAPI rewrite 3 and make the site treat .htm extensions as .aspx files. I slapped this in ISAPI and VOILA! Works a treat..
RewriteEngine on
RewriteRule ^(.*)\.htm $1\.aspx
Hope this helps someone else