Got unexpained "access denied" troubles keeping people from your content? Go to admin/content/node-settings, and try the 'Rebuild Permissions' button.
If that doesn't work, see other ideas for access denied for visitors and access denied for admins.

Nice list, some other modules I've found useful include:
Many of these should be included with drupal, it takes forever to set up a new site. For example webform is miles ahead of the built-in poll module. ed_readmore, ajax, video_filter, securepages, smtp, upload_replace commentrss etc. all do things that should be included with drupal, at least as an option (like with upload_replace). See for example moodle which out of the box supports smtp, ldap, built-in display of video/audio files, etc.
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Got unexpained "access denied" troubles keeping people from your content? Go to admin/content/node-settings, and try the 'Rebuild Permissions' button.
If that doesn't work, see other ideas for access denied for visitors and access denied for admins.
Hello! I just would like to give a huge thumbs up for the great info you have here on this post...
I may not have a chance to test that for a while, but meanwhile I welcome commentary from anyone...
Hey,
Since I still see some links here, and the guide is quite good, I thought that I may...
Nice article i like the way you thoroughly wrote it.