captcha image being blocked by IIS

I'm implementing captcha on my website like the one in https://web.ar开发者_开发百科chive.org/web/20210304122904/https://www.4guysfromrolla.com/articles/060706-1.aspx. It is working fine while running on VS2008. However, not when uploaded on IIS. I think the image is being blocked by IIS.. anyone knows how to fix this?

thanks

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Fixed it.. Issue with .net 4.0 http handler has to be included in system.webserver instead of system.web in web.config.

Thanks to:

http://www.codeproject.com/KB/custom-controls/CaptchaControl.aspx?msg=2117617 (Sectio: Image not displaying - IIS7).