文件上传转换失败，下载提示文件不存在，预览没反应
log日志：
2016-07-21 08:35:35,793 [5] INFO - - step6:ExecelToPDFConverter构造函数异常；异常原因：Retrieving the COM class factory for component with CLSID {00024500-0000-0000-C000-000000000046} failed due to the following error: 8000401a 因为配置标识不正确，系统无法开始服务器进程。请检查用户名和密码。 (Exception from HRESULT: 0x8000401A).
2016-07-21 08:35:35,793 [5] INFO - - step7:ExecelToPDFConverter的Convert方法出现异常；异常原因：Object reference not set to an instance of an object.
2016-07-21 08:36:03,854 [5] INFO - - step6:ExecelToPDFConverter构造函数异常；异常原因：Retrieving the COM class factory for component with CLSID {00024500-0000-0000-C000-000000000046} failed due to the following error: 8000401a 因为配置标识不正确，系统无法开始服务器进程。请检查用户名和密码。 (Exception from HRESULT: 0x8000401A).
2016-07-21 08:36:03,854 [5] INFO - - step7:ExecelToPDFConverter的Convert方法出现异常；异常原因：Object reference not set to an instance of an object.：
下载
2016-07-21 16:16:41,272 [291] ERROR - DBId:557b97bd00b021 - download file error.
System.Threading.ThreadAbortException: Thread was being aborted.
at System.Web.Hosting.UnsafeIISMethods.MgdExplicitFlush(IntPtr context)
at System.Web.Hosting.IIS7WorkerRequest.ExplicitFlush()
at System.Web.HttpResponse.Flush(Boolean finalFlush)
at System.Web.HttpWriter.WriteFromStream(Byte[] data, Int32 offset, Int32 size)
at Kingdee.BOS.FileServer.Web.Download.ReponseFileWithLimitedSpeed(String filePath, Int64 speed)
at Kingdee.BOS.FileServer.Web.Download.Page_Load(Object sender, EventArgs e)
然后紧接着的上传就是成功的，刚开始用几个月一直都没问题，后来更新补丁出现配置文件丢失之后就一直有此问题，请问有什么好办法解决吗，现在有小几率转换出错！！！