.net Facebook redirect handler not working if not in root of site - facebook

Question

I have a Facebook canvas app developed in /net using C# and the latest Facebook SDK 5.xyz
Everything was working fine when i had the app was running a website where all files were on root directory ( http://localhost:81/ ).
Now I had to move (adapt) my app to run from a subdir of an existing website ( http://localhost:81/MySiteFacebook/ )
in web.config i have
<handlers>
<add name="facebookredirect" path="facebookredirect.axd" verb="*" type="Facebook.Web.FacebookAppRedirectHttpHandler, Facebook.Web" />
But this way is not working, while the Authorization is doing the redirect i see in url:
http://www.facebook.com/dialog/oauth/?scope=user_about_me,publish_stream,email&state=STATEHASHHER&client_id=CLIENTIDHERE&redirect_uri=http://localhost:81/facebookredirect.axd
if i manulay add in the url at redirect_uri the subdir and come with: http://localhost:81/MySiteFacebook/facebookredirect.axd
The redirect works fine, it sends me to my registration page.
Given this behavior i went back to my web.config and added the /MySiteFacebook/facebookredirect.axd to the 'path' of the handled.
Guess what? it is not adding this path to the redirect_uri.. ? :(
Any idea? please , Thanks.

Answer 1

You're changing the web.config in the wrong place, you should be editing the urls in the facebookSettings such as:
<facebookSettings appId = "{app_id}" appSecret = "{app_secret}"
canvasPage = "http://apps.facebook.com/{canvas_page}/"
canvasUrl = "http://localhost:81/MySiteFacebook"
secureCanvasUrl = "https://localhost:81/MySiteFacebook" />