通过VB.net打印word文档中的活动打印机问题

\abcFirst Floor A-Block

Private oWord As Word.Application

Dim lobjDoc As Word.Document

Dim strFolder as String
Dim pd As New PrintDocument
Dim strPrintername as String
oWord = CreateObject("Word.Application")
oWord.DisplayAlerts = Word.WdAlertLevel.wdAlertsNone
oWord.ActivePrinter =strPrintername 
strFolder="D:testdoc.prn"

lobjDoc = oWord.Documents.Open(CType(strFolder, Object))

lobjDoc.PageSetup.FirstPageTray = Word.WdPaperTray.wdPrinterAutomaticSheetFeed

lobjDoc.PageSetup.OtherPagesTray = Word.WdPaperTray.wdPrinterAutomaticSheetFeed

lobjDoc.PrintOut(Background:=False, Append:=False, OutputFileName:=strFolder, PrintToFile:=True)  'here its giving error about printer settings

lobjDoc.Close(SaveChanges:=False)