What's the problem, exactly? Have you set @Codepage=65001 in the page directives at the top of your file? Have you marked the content-type with the correct encoding so that the client knows what its getting?
If you see question marks, it's probable that you haven't set the response code page correctly. If you see two unrelated characters in place of a single character with a diacritic , you haven't told the client what it needs to know to treat the page as UTF-8, e.g.
Response.CodePage = 65001 ;
Response.CharSet = "utf-8" ;
There are slight differences between asp.net and asp handling of encoding, so it would also be helpful if you were more specific about which technology you're using, but that should get you most of the way there.
In ASP.Net, you can set the encoding site-wide in your web.config file, so you can avoid messing with Response.CodePage and Request.CodePage on every page. You still want to mark the Response Charset using the meta http-equiv content-type element in your HTML or using Response.Charset.
<globalization
requestEncoding="utf-8"
responseEncoding="utf-8" />
If you don't want to use web.config for this for some reason, you'd use <%@CodePage=65001 %> in your .aspx file before you output any text, in the page directives.
It looks like the page in question contains incorrectly encoded UTF-8. Is the content coming straight from the .aspx file or is it being pulled from a database or something?