I tried a different way and everything worked out...
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Private Sub Form_Load()
Me.[ML-Sub].LinkMasterFields = vbNullString
Me.[ML-Sub].LinkChildFields = vbNullString
Me.[ML-Sub1].LinkMasterFields = vbNullString
Me.[ML-Sub1].LinkChildFields = vbNullString
End Sub
Private Sub BookType_AfterUpdate()
If Not Me.BookType = -1 Then
If Len(Me.[ML-Sub].LinkMasterFields) = 0 Then
Me.[ML-Sub].LinkMasterFields = Me.BookType.Name
Me.[ML-Sub].LinkChildFields = "[Type Id]"
End If
If Len(Me.[ML-Sub1].LinkMasterFields) = 0 Then
Me.[ML-Sub1].LinkMasterFields = Me.BookType.Name
Me.[ML-Sub1].LinkChildFields = "[Type Id]"
End If
Else
If Not Len(Me.[ML-Sub].LinkMasterFields) = 0 Then
Me.[ML-Sub].LinkMasterFields = vbNullString
Me.[ML-Sub].LinkChildFields = vbNullString
End If
If Not Len(Me.[ML-Sub1].LinkMasterFields) = 0 Then
Me.[ML-Sub1].LinkMasterFields = vbNullString
Me.[ML-Sub1].LinkChildFields = vbNullString
End If
End If
End Sub
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Thank you guys for responding and for your time spent...