Time after time when user do next code:

ox=createobject('word.document')
...
ox.application.ChangeFileOpenDirectory(lcpath_des)
ox.application.Documents.Open("dog_423.doc")
ox.application.Activedocument.printout

we have error:
OLE error code 0x800706ba Server RPC is not available
What operator is "guilty"?
Thanks for answers.