问题是Outlook com对象正在保留引用并阻止应用程序关闭.使用以下函数，并将您的"app"对象传递给它:

The issue is that the outlook com object is holding on to references and stopping the app from closing. Use the following function and pass your "app" object to it:

private void ReleaseObj(object obj)
{
    try 
    {
        System.Runtime.InteropServices.Marshal.ReleaseComObject(obj);
    }
    catch {}
    finally 
    {
        obj = null;
    }
}

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