I am unsure where goes wrong. Please kindly help and thanks.

Public Sub AddField() Dim pApp As esriCatalogUI.IGxApplication Set pApp = esriArcCatalog.Application

Dim pGxSelection As esriCatalog.IGxSelection Set pGxSelection = pApp.Selection

Dim plist As esriCatalog.IEnumGxObject Set plist = pGxSelection.SelectedObjects

Dim pGxObject As esriCatalog.IGxObject Dim pName As esriSystem.IName Dim pDS As esriGeoDatabase.IDataset Dim pGDSE As esriGeoDatabase.IGeoDatasetSchemaEdit Dim pStatusBar As esriSystem.IStatusBar Set pStatusBar = esriArcCatalog.Application.StatusBar

Dim pFeatLyr As esriCarto.IFeatureLayer Dim pFeatureClass As esriGeoDatabase.IFeatureClass Dim pFeatureDataset As esriGeoDatabase.IFeatureDataset
Dim pFieldEdit As esriGeoDatabase.IFieldEdit

Set pGxObject = plist.Next Set pFeatureClass = pGxObject

If pFeatureClass.Type = esriDTFeatureClass Then Set pFeatLyr = New FeatureLayer Set pFeatLyr.FeatureClass = pFeatureDataset.Dataset pFeatLyr.name = pGXDataset.Dataset.name

End If

'Checks to make sure you have something selected

If pGxObject Is Nothing Then MsgBox "You need to select the files", vbOKOnly, "Error" Exit Sub End If

'Runs a function to add field

Dim pField1 As esriGeoDatabase.IFieldEdit

' Define the first new field. Set pField1 = New Field pField1.Name = "GID1" pField1.Type = esriFieldTypeInteger pField1.Length = 10

pFeatureClass.AddField pField1

'Loops through all selected files and preforms Do Until pGxObject Is Nothing If TypeOf pGxObject Is esriCatalog.IGxDataset Then Set pName = pGxObject.InternalObjectName Set pDS = pName.Open Set pGDSE = pDS With pGDSE If .CanAlterSpatialReference Then .AlterSpatialReference pFieldEdit End If End With End If pStatusBar.Message(0) = "Done: " & pGxObject.Name Set pGxObject = plist.Next Loop

CleanUp: Set pFieldEdit = Nothing Set pGDSE = Nothing pStatusBar.Message(0) = "Done"

End Sub