Hi.
I have got a critical problem. Suddenly It is not possible to edit the content in existing HTML modules on the pages any more, but if I put a new module on a page, that module is working fine.
I have not changed any settings or anything on the server, so what could have happened? I hope that someone can give a quick solution to this problem.
Our DNN version is 5.6.1.

I get this error:
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.Html.EditHtml.grdVersions_ItemDataBound(Object sender, GridItemEventArgs e) at Telerik.Web.UI.RadGrid.OnItemDataBound(GridItemEventArgs e) at Telerik.Web.UI.GridItem.SetupItem(Boolean dataBind, Object dataItem, GridColumn[] columns, ControlCollection rows) at Telerik.Web.UI.GridItemBuilder.InitializeItem(Int32 dataSourceIndex, String& nextItemHierarchicalIndex, Boolean& itemIsInEditMode) at Telerik.Web.UI.GridItemBuilder.CreateItems(GridGroupingContext group) at Telerik.Web.UI.GridTableView.CreateItems(IEnumerator enumerator, GridColumn[] columns, ControlCollection controls) at Telerik.Web.UI.GridTableView.CreateControlHierarchy(Boolean useDataSource) at Telerik.Web.UI.GridTableView.CreateChildControls(IEnumerable dataSource, Boolean useDataSource) at System.Web.UI.WebControls.CompositeDataBoundControl.PerformDataBinding(IEnumerable data) at System.Web.UI.WebControls.DataBoundControl.OnDataSourceViewSelectCallback(IEnumerable data) at System.Web.UI.DataSourceView.Select(DataSourceSelectArguments arguments, DataSourceViewSelectCallback callback) at System.Web.UI.WebControls.DataBoundControl.PerformSelect() at Telerik.Web.UI.GridTableView.PerformSelect() at System.Web.UI.WebControls.BaseDataBoundControl.DataBind() at Telerik.Web.UI.GridTableView.DataBind() at Telerik.Web.UI.RadGrid.DataBind() at DotNetNuke.Modules.Html.EditHtml.DisplayVersions() at DotNetNuke.Modules.Html.EditHtml.Page_Load(Object sender, EventArgs e) --- End of inner exception stack trace ---

Thanks!

B.r.
Kurt

Yes, I have hard deleted a user (my own) because I tested a new login module (we wanted the users to be automatically logged in) so we got a trial of a login module that integrated to Active Directory and was able carry out auto login, but something wen't wrong and I was not able to log in any more and I couldnt delete or create my self the normal way, so I had to do it the hard way.
Thank you very much for the answer - now that I know the reason it might be more easy to solve the problem (maybe by upgrading as you suggested).

Thanks again :-)

B.r.
Kurt