This is one that bugged me years ago when I first started scripting. The problem was portability. I was not able to easily move my scripts from one location to another without having to go in and change me code for any external files the script referenced.
I first started off using a constant in the declarations section of the script. This helped. I simply put the folder location the script was in and used that constant throughout the script. I still had to do manual work. Finally I got smart and asked Windows where the script was being executed from. Below is the code that I used.
Dim AppPath ' Will store the path that the script and text file are located in.
Script Main Logic
' Determin the file path
AppPath = fGetPath
Functions and Sub Procedures
' Returns the path that the script is run from.
Set oShell = CreateObject("WScript.Shell")
GetPath = oShell.CurrentDirectory & "\"
End Function ' GetPath
Using this code, your script will know where it is at and make it portable without having to worry about where the script is stored or executed from.