Help to Search for and in a Text file for a desired string

Hello,

I am brand new to excel VBA, and have been doing some work for a company that i am an intern for with it, but i am having difficulties with figuring out how to write the second part of code for a program i am trying to write. Initially the program takes in 4 inputs from the User, puts them into empty cells 1-4 and in the 5th cell is a password that must be copied as an output and placed into a text (.h) file after a specific position in place of the old password. Oh but it also has to copy the old file and save it as old.h incase there is a problem. What i am having the most difficulty with is trying to make a program that will search for specific line and input the 4 digit string in place of the old string. Also i have no cluse how to copy a file into a new text file with a new name besides reading the old file and writing the new one, but then it runs in one consecutive line. I dont know if this makes sense so basically what i am trying to do is:

Make a program that:

1. Searches for A .h (text) file
2. Copies the .h file into another file to save a copy of the old file.
3. Reads through the text file until it finds a specific line.
4. After the line is read a 4 digit string from a predefined value replaces the one in the initial program.
5. Saves the new file.

I can give more information if needed, i am not someone that uses forums, so i dont know the best way to write my problem.

Hello Taylorez,

This macro will change the password in the file. There are two important pieces of information that needed for this to work. The location of the new and old passwords.

This macro will display the Open File dialog. You can then select the folder and file you want to open. The default files shown are *.h, *.txt, and *.csv. You also can choose "All Files".

'Written: October 12, 2010
'Author:  Leith Ross (www.execlforum.com)

Sub CopyAndModifyFile()

  Dim Data As Variant
  Dim FileFilter As String
  Dim FileName As String
  Dim FSO As Object
  Dim I As Long
  Dim oldpwd As String, newpwd As String
  Dim TextFile As Object

    oldpwd = "1234"
    newpwd = ActiveSheet.Range("E2")
    
    FileFilter = "Text files (*.h;*.txt;*.csv),*.h;*.txt;*.csv,All Files (*.*), *.*"
    FileName = Application.GetOpenFilename(FileFilter, 1)
    If FileName = "False" Then Exit Sub
    
      Set FSO = CreateObject("Scripting.FileSystemObject")
      
        FSO.CopyFile FileName, "old " & FSO.GetFileName(FileName)
       
        Set TextFile = FSO.OpenTextFile(FileName, 1, False, -2)
          Data = TextFile.ReadAll
        TextFile.Close
          
          I = InStr(1, Data, oldpwd)
          If I > 0 Then
             Set TextFile = FSO.OpenTextFile(FileName, 2, True, -2)
               Data = Left(Data, I - 1) & newpwd & Right(Data, I + Len(oldpwd))
               TextFile.Write Data
             TextFile.Close
          End If
      
End Sub

Hello Taylorez,

Is the old password always located in the same place?

Hello taylorez,

Can you post a couple of these old files? It will help me establish a pattern (if there is one).

Hello Taylorez,

Will this string be the only one in the file ending with _PASSWORT?