Then the LOOKFOR rule needs a little touch-up.  I just wrote that as a first draft without any checking.  For really getting RegEx right, you need to use a tool like RegEx Buddy (not free, but it is the best out there and cheaper than it could be), The Regulator (open source, buggy, and abandonded, but otherwise does the job fairly well), or RegEx Lib (free online regex validator).

FriendlyURLs should indeed be enabled for this to work.  That's fine.  I am glad you used RegEx Buddy.  That is a great tool.  Let's get back to the actual problem though...

When you say "no result", what does that mean?  Are you redirected to the home page?  Are you faced with a 404 error?  What happens?

This will work.

    <RewriterRule>
      <LookFor>.*ArticleDetail\.aspx.*(itemid=(\d+)).*</LookFor>
      <SendTo>~/Default.aspx?tabid=69&amp;ArticleID=$1</SendTo>
    </RewriterRule>

However, if the original URL contains the MID querystring value, DNN will react to it and not display the page properly.

I should add that I used to be able to explicitly specify the URL (instead of using the tilde ~), then the rewritten URL would completely replace the original.  I just tested this on a 4.08.03 install and it didn't do it, but the rewrite still took place.  Here is an example of what I am talking about.

    <RewriterRule>
      <LookFor>.*ArticleDetail\.aspx.*(itemid=(\d+)).*</LookFor>
      <SendTo>http://www.YourDomain.com/Default.aspx?tabid=69&amp;ArticleID=$1</SendTo>
    </RewriterRule>