File checking on Windows Startup is failing [duplicate]

Answer 1

it's on the same directory where the script above is located

This is not where a relative path looks. It starts from the working directory.

The working directory of a shortcut is not necessarily the directory containing the shortcut. You should edit the shortcut properties and set the working directory you want, instead of using the default (which is often C:\Windows or C:\Users\%USERNAME%)

Or you can put an absolute path in the script, or have the script change working directory to its own directory, or have the script combine its directory and the filename to dynamically create an absolute path.

Answer 2

The problem is because when you register your script on Windows Startup through the registry, the script will be executed from the directory of Windows Startup when windows started.

In order to get the original working directory where you can look for the auto_backup.bat, you can combine the FileSystemObject and WScript.ScriptFullName functions to get the parent directory of the current script.

CreateObject("Scripting.FileSystemObject").GetParentFolderName(WScript.ScriptFullName) & "\auto_backup.bat"

Then the IF-ELSE condition inside your loop would be

...
Do While True 
Set FSO = CreateObject("Scripting.FileSystemObject")
 
' (1) Add this code.
autobackup_bat_file = CreateObject("Scripting.FileSystemObject").GetParentFolderName(WScript.ScriptFullName) & "\auto_backup.bat"

If fso.FileExists(autobackup_bat_file) Then ' (2) Change this line.
    MsgBox "Backup Message Test."
    Set WshShell = CreateObject("WScript.Shell") 
    WshShell.Run chr(34) & autobackup_bat_file  & Chr(34), 0 ' (3) Change this line.

' Continue some of your code here...
...