Trying To Add to a File

Im trying to write to the end of a .DWG file to add a small
string this string will allow the teacher to end plagurism in his class but every time i write to the file using methods i know it deletes the entire file (with the exception of the string i added) does anybody know a way to make this work. If so please reply

If it is a simple text file then you can open this file in Append mode.

Code:

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Dim intFFN As Integer
Dim strPath As String

strPath = "C:\MyFile.txt"
intFFN = FreeFile

Open strPath For Append As intFFN
Print #intFFN, "This is an edition to the file."
Close #intFFN

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