I'm writing a small application extension and the only way to include some help is by a local, static html page (like c:\program files\help.htm). I can't use PHP for it. Is there any way to redirect such a page to an online page?
Sure, you can use html meta tag to instruct the browser to redirect to another page. Put this in your <head>
<meta http-equiv="refresh" content="0; url=http://example.com/">
Related question: How to redirect from .html page?