出错参考：http://bbs.kesion.com/forumthread-278623.html

下载系统的修改文件为

item/download.asp

找到代码

  Sub downloadFile(strFile,FileOldName)

   On error resume next

   Server.ScriptTimeOut=999999

   Dim S,fso,f,intFilelength,strFilename,DownFileName

   strFilename = strFile

   Response.Clear

   Set s = Server.CreateObject("ADODB.Stream")

   s.Open

   s.Type = 1

   Set fso = Server.CreateObject("Scripting.FileSystemObject")

   If Not fso.FileExists(strFilename) Then

     Response.Write("<h1>错误: </h1><br>系统找不到指定文件")

     Exit Sub

   End If

   Set f = fso.GetFile(strFilename)

     intFilelength = f.size

     s.LoadFromFile(strFilename)

     If err Then

      Response.Write("<h1>错误: </h1>" & err.Description & "<p>")

      Response.End

     End If

     Set fso=Nothing

     Dim Data

     Data=s.Read

     s.Close

     Set s=Nothing

     If FileOldName="" Or IsNull(FileOldName) Then DownFileName=f.name Else DownFileName=FileOldName

     If Response.IsClientConnected Then

      Response.AddHeader "Content-Disposition", "attachment; filename=" &  DownFileName

      Response.AddHeader "Content-Length", intFilelength

      Response.CharSet = "UTF-8"

      Response.ContentType = "application/octet-stream"

      Response.BinaryWrite Data

      Response.Flush

     End If

   End Sub

修改为：

Sub downloadFile(strFile,FileOldName)

   Dim fso,f,intFilelength,strFilename,DownFileName

   Set fso = Server.CreateObject("Scripting.FileSystemObject")

   If Not fso.FileExists(strFile) Then

     Response.Write("<h1>错误: </h1><br>系统找不到指定文件")

     Exit Sub

   End If

   Set f = fso.GetFile(strFile)

   Set fso=Nothing

      If KS.IsNul(FileOldName) Then DownFileName=f.name Else DownFileName=FileOldName

      Dim Stream,offset,TotalSize,ChunkSize ,strChunk

   Response.Buffer=False '将Response.Buffer设为否

   Response.ContentType = "application/octet-stream"

   response.AddHeader "Content-Disposition","attachment;filename=" & DownFileName

   Set Stream = Server.CreateObject("ADODB.Stream")

   Stream.type=1

   Stream.Open

   Stream.LoadFromFile strFile

   offset = 0

   ChunkSize = 2048*1024 'ChunkSize小于IIS配制文件中的AspBufferingLimit项所设置的大小

   TotalSize = Stream.Size

   while offset < TotalSize

   if (TotalSize - offset < ChunkSize) then

   ChunkSize = TotalSize-offset

   end if

   strChunk = Stream.Read(ChunkSize)

   Response.BinaryWrite strChunk

   offset = offset + ChunkSize

   wend

   Stream.Close

  End Sub

如果是论坛里的下载附件，则修改

item/filedown.asp,修改方法和上面一样。