Hello everyone

We are running a forum using latest DNN version and Forum module. We are facing problem while creating new section in forums. Whenever we try to create a new section by clicking on "Add Forum", it shows following error:

A critical error has occurred.
Object reference not set to an instance of an object.

We checked the Event Log viewer and found following information:

MODULE LOAD EXCEPTION:

ModuleId: 583
ModuleDefId: 131
FriendlyName: Edit Forum
ModuleControlSource: DesktopModules/Forum/Forum_ForumEdit.ascx
AssemblyVersion: 04.08.04
PortalID: 0
PortalName: xxx
UserID: 596
UserName: xxx
ActiveTabID: 324
ActiveTabName: Forums
RawURL: /Forums/tabid/324/ctl/ForumEdit/mid/583/forumid/92/Default.aspx
AbsoluteURL: /Default.aspx
AbsoluteURLReferrer: xxx/Default.aspx?TabId=324&ctl=ForumManage&mid=583
UserAgent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; Avant Browser; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.0.04506; Tablet PC 2.0; MS-RTC LM 8)
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider
ExceptionGUID: ab821e15-0c38-4544-beed-c9431528578e
InnerException: Object reference not set to an instance of an object.
FileName:
FileLineNumber: 0
FileColumnNumber: 0
Method: DotNetNuke.Modules.Forum.ForumEdit.PopulateForum
StackTrace:
Message: DotNetNuke.Services.Exceptions.ModuleLoadException: 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.ForumEdit.PopulateForum() at DotNetNuke.Modules.Forum.ForumEdit.Page_Load(Object sender, EventArgs e) --- End of inner exception stack trace ---
Source:
Server Name: INDIACOMMUNITY

PAGE LOAD EXCEPTION:

AssemblyVersion: 04.08.04
PortalID: 0
PortalName: xxx
UserID: 596
UserName: xxx
ActiveTabID: 324
ActiveTabName: Forums
RawURL: /Forums/tabid/324/ctl/ForumEdit/mid/583/forumid/92/Default.aspx
AbsoluteURL: /Default.aspx
AbsoluteURLReferrer: xxx/Default.aspx?TabId=324&ctl=ForumManage&mid=583
UserAgent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; Avant Browser; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.0.04506; Tablet PC 2.0; MS-RTC LM 8)
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider
ExceptionGUID: 91873c9c-af27-4ed9-8e27-fce4b4630caf
InnerException: Object reference not set to an instance of an object.
FileName:
FileLineNumber: 0
FileColumnNumber: 0
Method: DotNetNuke.Modules.Forum.Controls.ForumPermissionsGrid.Savev13wstat3
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.Controls.ForumPermissionsGrid.Savev13wstat3() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Control.Savev13wstat3Recursive() at System.Web.UI.Page.SaveAllState() at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) --- End of inner exception stack trace ---
Source:
Server Name: INDIACOMMUNITY

Can you guys please help and tell whats the cause of this problem and what can we do to fix it?

Thanks.

No. We are regularly updating the DNN software whenever a new version is released. Actually we don't create new forum sections frequently, so we can't tell exactly when the problem started. A few days back we tried to create a new section and we faced this problem.

I have the same problem, and it's very similar to this:

http://www.dotnetnuke.com/Community/Forums/tabid/795/forumid/7/threadid/197003/scope/posts/threadpage/6/Default.aspx

You may find that you can't edit existing forums either.  Expand one of your existing groups and click the edit button for one of the existing forums.  I get the same errors.  Apparently it has to do with the permissions tables, but I've looked at mine and they look ok.  In fact, they look very similar to my dev system which has a new install of the forum (never upgraded) which works fine.

Sorry I'm no help right now, I'm still trying to figure it out myself.

Chris