What is the best way to add \"Expires\" in http header for static content? eg. images, css, js
The web server is IIS 6.0; the language is classical ASP
I think this is what you're after, It's Content Expiration under HTTP Headers in IIS Manager. I use the pattern of sticking static content under a folder like ~/Resources and setting the expiration on that particular folder to have a much longer life than the rest of the application.
Here's a link to the full article: IIS 6.0 F1: Web Site Properties - HTTP Headers Tab