word转换为HTML，本地测试可以，请教放服务器下为什么无法使用

 public void wordchangetohtml(string sourcepath, string htmlpath)    {        try        {            Word.ApplicationClass word = new Word.ApplicationClass();            Type wordType = word.GetType();            Word.Documents docs = word.Documents;            // 打开文件            Type docsType = docs.GetType();            object fileName = sourcepath;            Word.Document doc = (Word.Document)docsType.InvokeMember("Open",            System.Reflection.BindingFlags.InvokeMethod, null, docs, new Object[] { fileName, true, true });            // 转换格式，另存为            Type docType = doc.GetType();            object saveFileName = htmlpath;            ///wdFormatUnicodeText            docType.InvokeMember("SaveAs", System.Reflection.BindingFlags.InvokeMethod, null, doc, new object[] { saveFileName, Word.WdSaveFormat.wdFormatHTML });            // 退出 Word            wordType.InvokeMember("Quit", System.Reflection.BindingFlags.InvokeMethod, null, word, null);        }        catch (Exception EX)        {            throw EX;        }    }