Method: DotNetNuke.Modules.Forum.Posts.RenderPostAuthor
StackTrace:
Message: DotNetNuke.Services.Exceptions.PageLoadException: Object reference not set to an instance of an object. ---> System.NullReferenceException: Object reference not set to an instance of an object. at DotNetNuke.Modules.Forum.Posts.RenderPostAuthor(HtmlTextWriter wr, PostInfo Post, Boolean PostCountIsEven) at DotNetNuke.Modules.Forum.Posts.RenderPost(HtmlTextWriter wr, PostInfo Post, Boolean PostCountIsEven) at DotNetNuke.Modules.Forum.Posts.RenderPosts(HtmlTextWriter wr) at DotNetNuke.Modules.Forum.Posts.RenderThread(HtmlTextWriter wr) at DotNetNuke.Modules.Forum.Posts.Render(HtmlTextWriter wr) at DotNetNuke.Modules.Forum.ForumBaseControl.Render(HtmlTextWriter wr) at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer) at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) at System.Web.UI.Control.Render(HtmlTextWriter writer) at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer) at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) at System.Web.UI.Control.Render(HtmlTextWriter writer) at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer) at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) at System.Web.UI.UpdatePanel.RenderChildren(HtmlTextWriter writer) at System.Web.UI.Control.Render(HtmlTextWriter writer) at System.Web.UI.UpdatePanel.Render(HtmlTextWriter writer) at

I haven't been able to reproduce this:

1. Are you using avatars? 
   1. If so, is it core profile avatars?
      1. Did you set it to the photo property too? 
2. Does the host userid exist in the Forum_Users table for the same portalID? 
3. Can you reproduce the problem w/ a non-host?
   1. If no, how about using another host user?
4. Can the user do everything else (basically, posting and viewing posts or possibly moderation) except view their own posts?
   1. If yes, can they use "My Posts" or show up in post search results by others?