Hello good people of Dotnetnuke, am having the below problem in my forum and have no ideas what's causing it.  This is happening only on one thread and am thinking it's something to do the last post a member posted.

Any help would be much appreciated.

Thanks.  

AssemblyVersion: 04.08.00
PortalID: 0
PortalName:
UserID: -1
UserName:
ActiveTabID: 54
ActiveTabName: Forum
RawURL: /Forum/tabid/54/forumid/6/scope/threads/language/en-GB/Default.aspx
AbsoluteURL: /Default.aspx
AbsoluteURLReferrer: http://www.najivunia.co.uk/Forum/tabid/54/forumid/6/scope/threads/Default.aspx
UserAgent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; WOW64; SLCC1; .NET CLR 2.0.50727; .NET CLR 3.0.04506; Media Center PC 5.0; InfoPath.2)
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider
ExceptionGUID: 395be457-f124-42ed-b547-08d0fc4ba42b
InnerException: Value cannot be null. Parameter name: value
FileName:
FileLineNumber: 0
FileColumnNumber: 0
Method: System.Web.Caching.CacheEntry..ctor
StackTrace:
Message: System.ArgumentNullException: Value cannot be null. Parameter name: value at System.Web.Caching.CacheEntry..ctor(String key, Object value, CacheDependency dependency, CacheItemRemovedCallback onRemovedHandler, DateTime utcAbsoluteExpiration, TimeSpan slidingExpiration, CacheItemPriority priority, Boolean isPublic) at System.Web.Caching.CacheInternal.DoInsert(Boolean isPublic, String key, Object value, CacheDependency dependencies, DateTime utcAbsoluteExpiration, TimeSpan slidingExpiration, CacheItemPriority priority, CacheItemRemovedCallback onRemoveCallback, Boolean replace) at System.Web.Caching.Cache.Insert(String key, Object value, CacheDependency dependencies) at DotNetNuke.Services.Cache.FileBasedCachingProvider.FBCachingProvider.Insert(String CacheKey, Object objObject, Boolean PersistAppRestart) at DotNetNuke.Common.Utilities.DataCache.SetCache(String CacheKey, Object objObject) at DotNetNuke.Modules.Forum.ThreadInfo.GetThreadInfo(Int32 ThreadID) at DotNetNuke.Modules.Forum.Threads.RenderThreadInfo(HtmlTextWriter wr, Boolean AggregatedView)
Source:
Server Name: WEBSERVER

OK, no replies yet so... How do you go about the solution below...

Thanks...

The Exception logs on dnn.com show a number of errors from trying to cache a null object - for example

Message: System.Exception: Unhandled Error: ---> System.Web.HttpUnhandledException: Exception of type 'System.Web.HttpUnhandledException' was thrown. ---> System.ArgumentNullException: Value cannot be null. Parameter name: value at System.Web.Caching.CacheEntry..ctor(String key, Object value, CacheDependency dependency, CacheItemRemovedCallback onRemovedHandler, DateTime utcAbsoluteExpiration, TimeSpan slidingExpiration, CacheItemPriority priority, Boolean isPublic) at System.Web.Caching.CacheInternal.DoInsert(Boolean isPublic, String key, Object value, CacheDependency dependencies, DateTime utcAbsoluteExpiration, TimeSpan slidingExpiration, CacheItemPriority priority, CacheItemRemovedCallback onRemoveCallback, Boolean replace) at System.Web.Caching.Cache.Insert(String key, Object value, CacheDependency dependencies) at DotNetNuke.Services.Cache.FileBasedCachingProvider.FBCachingProvider.Insert(String CacheKey, Object objObject, Boolean PersistAppRestart) at DotNetNuke.Common.Utilities.DataCache.SetCache(String CacheKey, Object objObject) at DotNetNuke.Modules.Forum.ForumInfo.GetForumInfo(Int32 ForumID)

and

Message: DotNetNuke.Services.Exceptions.PageLoadException: Value cannot be null. Parameter name: value ---> System.ArgumentNullException: Value cannot be null. Parameter name: value at System.Web.Caching.CacheEntry..ctor(String key, Object value, CacheDependency dependency, CacheItemRemovedCallback onRemovedHandler, DateTime utcAbsoluteExpiration, TimeSpan slidingExpiration, CacheItemPriority priority, Boolean isPublic) at System.Web.Caching.CacheInternal.DoInsert(Boolean isPublic, String key, Object value, CacheDependency dependencies, DateTime utcAbsoluteExpiration, TimeSpan slidingExpiration, CacheItemPriority priority, CacheItemRemovedCallback onRemoveCallback, Boolean replace) at System.Web.Caching.Cache.Insert(String key, Object value, CacheDependency dependencies) at DotNetNuke.Services.Cache.FileBasedCachingProvider.FBCachingProvider.Insert(String CacheKey, Object objObject, Boolean PersistAppRestart) at DotNetNuke.Common.Utilities.DataCache.SetCache(String CacheKey, Object objObject) at DotNetNuke.Modules.Forum.ThreadInfo.GetThreadInfo(Int32 ThreadID)

The GetThreadInfo code looks like this:

        Public Shared Function GetThreadInfo(ByVal ThreadID As Integer) As ThreadInfo
            Dim strCacheKey As String = ThreadInfoCacheKeyPrefix & CStr(ThreadID)
            Dim objThread As ThreadInfo = CType(DataCache.GetCache(strCacheKey), ThreadInfo)

            If objThread Is Nothing Then
                Dim ctlThread As New ThreadController
                objThread = ctlThread.ThreadGet(ThreadID)
                DataCache.SetCache(strCacheKey, objThread)
            End If

            Return objThread
        End Function

and the GetForumInfo code is very similar.

There are two problems with this code:

1. There is no check the object returned is not null before attempting to save it to the cache.
2. The code does not respect the Host users selection for cache performance.

Thus GetThreadInfo should be changed to:

        Public Shared Function GetThreadInfo(ByVal ThreadID As Integer) As ThreadInfo
            Dim strCacheKey As String = ThreadInfoCacheKeyPrefix & CStr(ThreadID)
            Dim objThread As ThreadInfo = CType(DataCache.GetCache(strCacheKey), ThreadInfo)

            If objThread Is Nothing Then
                'thread caching settings
                Dim timeOut As Int32 = ThreadInfoCacheTimeout * Convert.ToInt32(Common.Globals.PerformanceSetting)

                Dim ctlThread As New ThreadController
                objThread = ctlThread.ThreadGet(ThreadID)

                'Cache Thread if tmeout > 0 and Thread is not null
                If timeOut > 0 And objThread IsNot Nothing Then
                    DataCache.SetCache(strCacheKey, objThread, TimeSpan.FromMinutes(timeOut), False)
                End If
            End If

            Return objThread
        End Function

Note: PostInfo has the 2nd issue (performance setting) but does not have the first issue.

Hi DNN Team,

These errors:

InnerException: Value cannot be null. Parameter name: value

and

InnerException: Unhandled Error:

make the dotnetnuke forums unreliable and unusable.

I have now spent hours deleting posts to address these errors and to get my forums up and running again.

What is the resolution for these errors?