Tip - HowTo Enable Anonymous Access to discussion board listview within a public readonly publishing site

For a public exposed website you'll need to enable anonymous access, to allow arbitrair visitors to see the published content, and search crawlers to index your site. You'll also want the site visitors to only be able to view the site contents, not to modify it.

There are some exceptions to this general permission rule. One is when the website contains 1 or more discussion boards. To enable any arbitrair visitor to participate in a discussion thread, she needs update permission rights within the SharePoint DiscussionBoard. In a former project we learned that it's not trivial to enable update rigths for anonymous users in a further readonly publishing SharePoint site. To spare you the time to discover yourself how to still achieve this, I decided to publish here the steps I needed to perform.

1. [Central Admin] create new web app
2. [Central Admin] create a site collection with Publishing Portal as template
3. [Central Admin] extend the web application for internet; and allow Anonymous.
   

   Note: in this stadium still WA allowed at the extended site.

4. [Site itself] open up the extended site; since WA allowed possible to change settings
5. [Site itself] enable anonymous access for entire site
   (site settings \ advanced settings \ settings \ Anonymous Access \ Entire Website)
6. [Central Admin] disable Integrated WA for the extended site to make it totally anonymous
7. [Shell/CMD on SharePoint server] !! toggle the lockdown feature on the extended site; and do either app pool recycle or IIS reset
8. [Site itself] provision a DiscussionBoard, and set its permission to allow anonymous access.
9. [Central Admin] re-enable WA on the extended site
10. [Site itself] allow anonymous access for both viewing and adding items on the discussionboard list
11. [Central Admin] disable again WA

This sequence of steps, and in this exact order, worked out for us. When deviating from it, we still experienced access denied issues; either upon trying to display the discussionboard ListView, or when trying to add a new thread or reply to existing discussion.

See also: Allow anonymous user access to display forms of discussion board list(view)