Following script can be used to append entries in HOSTS file.
A text file containing the entry to be appended should be placed in INPUT location as in below script
Const ForReading = 1, ForWriting = 2, ForAppending = 8
Dim TargetFile,objWshShell,objFSO, Input, ProgramFiles, WinDir
Dim objTextFile, Target
Set objWshShell = CreateObject("WScript.Shell")
Set objFSO = CreateObject("Scripting.FileSystemObject")
ProgramFiles = ObjWshShell.ExpandEnvironmentStrings("%ProgramFiles%")
WinDir = ObjWshShell.ExpandEnvironmentStrings("%WinDir%")
Set Targetfile = objFSO.GetFile(WinDir & "\system32\drivers\etc\hosts")
Set Input = objFSO.GetFile(ProgramFiles & "\Input.txt")
Set objTextFile = objFSO.OpenTextFile (Input, ForReading)
Set Target = CreateObject("Scripting.FileSystemObject")
Set TargetFile = Target.OpenTextFile (TargetFile, ForAppending, True)
Do Until objTextFile.AtEndOfStream
Input = objTextFile.ReadLine
TargetFile.WriteLine(Input)
Loop
TargetFile.Close
ObjTextFile.Close
objFSO.DeleteFile(ProgramFiles & "\Input.txt")
