I have used the code below for a few years in an ArcGIS Engine application we have developed. Essentailly it builds a sorted IEnumerator of unique values from a specific field in a layers attribute table. It has worked fine for years however after upgrading to SP-1 of 10.1 running it consecutivly three times to build three differant lists of values it causes our application to crash. The crash seems to happed a few seconds after we step through the last IEnumerator to populate a listbox.Am I missing somthing here? The crash is an "nt.dll" error in a standard windows error box.private IEnumerator getSortedList(string mField, ILayer mLayer, string whereclause) { IQueryFilter mQFilter = new QueryFilterClass(); mQFilter.WhereClause = whereclause; IEnumerator mEnumstreets = null; if (mLayer != null) { IFeatureLayer mFeatureLayer = (IFeatureLayer)mLayer; IFeatureClass pFeatureClass = mFeatureLayer.FeatureClass; if (pFeatureClass != null) { ITable pTable = (ITable)pFeatureClass; IFeatureCursor pCursor = pFeatureClass.Search(mQFilter, true); ITableSort mTableSort = new TableSortClass(); mTableSort.Table = pTable; mTableSort.Fields = mField; mTableSort.set_Ascending(mField, true); mTableSort.QueryFilter = mQFilter; mTableSort.Sort(null); IDataStatistics mDataStats = new DataStatisticsClass(); mDataStats.Cursor = mTableSort.Rows; mDataStats.Field = mField; mEnumstreets = mDataStats.UniqueValues; pCursor = null; } } return mEnumstreets; }