Good afternoon everyone ,the following code will prompt user cancelled error,please help me,thanks!

IEdmBatchAdd poAdder = poVault.CreateUtility(EdmUtility.EdmUtil_BatchAdd) as IEdmBatchAdd;

            poAdder.AddFileFromPath("d:\test1.dwg", lParentFolderID, 333, "copy of test1.dwg", 256);
            poAdder.AddFileFromPath("d:\test2.dwg", lParentFolderID, 333, "copy of test2.dwg", 256);
            poAdder.AddFileFromPath("d:\test3.dwg", lParentFolderID, 333, "copy of test3.dwg", 256);
            poAdder.AddFileFromPath("d:\test4.dwg", lParentFolderID, 333, "copy of test4.dwg", 256);

           Array aoItems = Array.CreateInstance(typeof(EdmFileInfo),4);     
           poAdder.CommitAdd(0, aoItems, 0, null);

            string msg = "";
            string row ="" ;

            foreach (EdmFileInfo s in aoItems)
            {
                 row= "(" + s.mbsPath + ") arg=" + s.mlArg.ToString()+ "result="+s.mhResult;
                 msg = msg + row;
            }

MessageBox.Show(msg);