<% 
Dim ValidEntry ' Log variable 
' First set that this log is valid 
ValidEntry = True 

' If Session Variable "LogIn" is not empty 
' that mean this person has already been logged 
' then set ValidLog to False 
If not IsEmpty(Session("LogIn")) then ValidEntry = False 

' Here you can add different restriction 
' If the refering url is from same site 
' don't write to log file 
If Left(Request.ServerVariables("HTTP_REFERER"), 17) 
="http://vevb.com" Then 
ValidEntry = False 
End if 
If Left(Request.ServerVariables("HTTP_REFERER"), 21) 
="http://www.companysz.com" Then 
ValidEntry = False 
End If 

' Now if ValidEntry is True then enter to log file 
If ValidEntry Then 
Const ForAppending = 8 
Const Create = true 
Dim FSO 
DIM TS 
DIM MyFileName 
Dim strLog 

MyFileName = Server.MapPath("MyLogFile.txt") 
Set FSO = Server.CreateObject("Scripting.FileSystemObject") 
Set TS = FSO.OpenTextFile(MyFileName, ForAppending, Create) 

' Store all required values in strLog 
strLog = "<br><P><B>" & now & "</B> " 
strLog = strLog & Request.ServerVariables("REMOTE_ADDR") & " " 
strLog = strLog & Request.ServerVariables("HTTP_REFERER") & " " 
strLog = strLog & Request.ServerVariables("HTTP_USER_AGENT") & "<BR>" 
' Write current information to Log Text File. 
TS.write strLog 
TS.Writeline "" 
' Create a session varialbe to check next time for ValidEntry 
Session("LogIn") = "yes" 
Set TS = Nothing 
Set FSO = Nothing 
End If 
%>