I have an enterprise wiki with pages and categories and i would like the categories web part on the front page. As far as i can tell the categories and the rest of the wiki work fine, but when adding the categories web part i get the "Unable to display web part" error and the ULS logs shows the following exception:
Error while executing web part: 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, DateTime absoluteExpiration, TimeSpan slidingExpiration, CacheItemPriority priority, CacheItemRemovedCallback onRemoveCallback)
at Microsoft.SharePoint.Portal.WebControls.CategoryWebPartDataSourceView.AddSiteMapNodeCollectionToCache(String valueKey, SiteMapNodeCollection coll)
at Microsoft.SharePoint.Portal.WebControls.CategoryWebPartDataSourceView.GetRootLevelElements(RootElementData rootElementData)
at Microsoft.SharePoint.Publishing.Internal.WebControls.RootElementData.GetChildren()
at Microsoft.SharePoint.Publishing.WebControls.LevelHierarchyWebPart.hierarchicalViewToXPathNavigator(HierarchicalDataSourceView hierView)
at Microsoft.SharePoint.Publishing.WebControls.LevelHierarchyWebPart.GetXPathNavigator(String viewPath)
at Microsoft.SharePoint.WebPartPages.DataFormWebPart.PrepareAndPerformTransform(Boolean bDeferExecuteTransform)
As far as i can tell that is the only error in the logs and I can't seem to figure out why this happens.
I haven't lost 'till I'm the last one to cross the finish line.