主题：[追问]远程升级，如何避免升级文件不存在时的报错

先检测

Dim url As String = "http://www.foxtable.com/download/release.rar"
try
    Dim rqst As System.Net.HttpWebRequest = System.Net.HttpWebRequest.Create(url)
    Dim rsps As System.Net.HttpWebResponse = rqst.GetResponse
catch ex As Exception
    msgbox(ex.message)
End try