文件服务器预览出错

图片和pd可以在线预览，就是word和excel不行
cloud日志报错：2017-12-15 08:33:28,527 [10] INFO - DBId:5a1fc57952c0b8 - UpdateFileServerInfoCache
2017-12-15 08:33:29,401 [10] INFO - DBId:5a1fc57952c0b8 - UpdateFileServerInfoCache:False
2017-12-15 08:38:00,436 [8] INFO - - step6：WordToPDFConverter构造函数出现异常；异常原因：Retrieving the COM class factory for component with CLSID {000209FF-0000-0000-C000-000000000046} failed due to the following error: 80070005 拒绝访问。 (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED)).
2017-12-15 08:38:00,436 [8] INFO - - step7：WordToPDFConverter的Convert方法失败;失败原因是：Object reference not set to an instance of an object.
2017-12-15 08:38:36,597 [30] INFO - - step6：WordToPDFConverter构造函数出现异常；异常原因：Retrieving the COM class factory for component with CLSID {000209FF-0000-0000-C000-000000000046} failed due to the following error: 80070005 拒绝访问。 (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED)).
2017-12-15 08:38:36,612 [30] INFO - - step7：WordToPDFConverter的Convert方法失败;失败原因是：Object reference not set to an instance of an object.
2017-12-15 08:38:58,187 [27] INFO - - step6：WordToPDFConverter构造函数出现异常；异常原因：Retrieving the COM class factory for component with CLSID {000209FF-0000-0000-C000-000000000046} failed due to the following error: 80070005 拒绝访问。 (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED)).
2017-12-15 08:38:58,187 [27] INFO - - step7：WordToPDFConverter的Convert方法失败;失败原因是：Object reference not set to an instance of an object.
2017-12-15 09:20:18,654 [10] INFO - DBId:5a09454145072b - UpdateFileServerInfoCache
2017-12-15 09:20:19,543 [10] INFO - DBId:5a09454145072b - UpdateFileServerInfoCache:False
2017-12-15 09:44:40,720 [10] INFO - DBId:5a09454145072b - UpdateFileServerInfoCache
2017-12-15 09:44:41,625 [10] INFO - DBId:5a09454145072b - UpdateFileServerInfoCache:False
2017-12-15 09:44:42,295 [8] INFO - - step6：WordToPDFConverter构造函数出现异常；异常原因：Retrieving the COM class factory for component with CLSID {000209FF-0000-0000-C000-000000000046} failed due to the following error: 80070005 拒绝访问。 (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED)).
2017-12-15 09:44:42,311 [8] INFO - - step7：WordToPDFConverter的Convert方法失败;失败原因是：Object reference not set to an instance of an object.
2017-12-15 09:53:41,838 [12] INFO - DBId:5a1fc57952c0b8 - UpdateFileServerInfoCache
2017-12-15 09:53:41,869 [12] INFO - DBId:5a1fc57952c0b8 - UpdateFileServerInfoCache:False
2017-12-15 09:53:42,087 [50] INFO - - step6：WordToPDFConverter构造函数出现异常；异常原因：Retrieving the COM class factory for component with CLSID {000209FF-0000-0000-C000-000000000046} failed due to the following error: 80070005 拒绝访问。 (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED)).
2017-12-15 09:53:42,087 [50] INFO - - step7：WordToPDFConverter的Convert方法失败;失败原因是：Object reference not set to an instance of an object.