Alright, let's troubleshoot this step by step—registry changes failing when calling batch files via VBS usually boils down to permissions, syntax issues, or incorrect execution context. Here's what to check:

Modifying even user-specific registry keys like HKCU often requires elevated privileges, especially if your batch targets system-related settings. By default, VBS scripts run with standard user permissions, which can block registry writes entirely.

Fix this by forcing your batch files to run as administrator from the VBS script. Replace your existing execution code with this:

Set objShell = CreateObject("Shell.Application")
' Call day batch with admin rights (update path to your actual file)
objShell.ShellExecute "cmd.exe", "/c ""C:\Full\Path\To\Day_Wallpaper.bat""", "", "runas", 1
' Call night batch (adjust path as needed)
objShell.ShellExecute "cmd.exe", "/c ""C:\Full\Path\To\Night_Wallpaper.bat""", "", "runas", 1

The runas flag triggers a UAC elevation prompt, ensuring the batch has the necessary rights to modify the registry.

First, confirm your batch files work when run manually (right-click > Run as administrator). If they don't, fix that first. Here's a reliable template for wallpaper-changing batches:

@echo off
REM Set path to your wallpaper (use quotes if path has spaces)
set "WALLPAPER_PATH=C:\Wallpapers\Sunny_Morning.jpg"

REM Update the registry key for your user account
reg add "HKCU\Control Panel\Desktop" /v Wallpaper /t REG_SZ /d "%WALLPAPER_PATH%" /f

REM Force desktop to refresh and apply the new wallpaper immediately
RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters 1, True

Key notes:

• Use HKCU (HKEY_CURRENT_USER) instead of HKLM—it requires fewer permissions and only affects your account.
• The /f flag in reg add is critical—it overwrites the existing value without prompting.
• The UpdatePerUserSystemParameters command ensures the desktop refreshes right away; without it, registry changes won't show up until you log out/in.

• Always use absolute paths: Relative paths break if the script runs from a different working directory (like the Startup folder).
• Escape quotes correctly: If your batch or wallpaper path has spaces, wrap the path in double quotes, and escape those quotes in VBS by using two double quotes (""), as shown in the VBS example above.
• Avoid WScript.Shell.Run: This method doesn't support elevation natively—stick with Shell.Application.ShellExecute for admin rights.

1. Run your batch file manually as administrator. Open regedit and navigate to HKCU\Control Panel\Desktop to verify the Wallpaper value updated.
2. If the batch works, run the VBS script manually. Accept the UAC prompt, then check the registry again.
3. If the VBS works manually but fails on startup, the issue is with how it's launched at boot.

Instead of relying on the Startup folder or registry Run keys (which can have permission gaps), use Task Scheduler for more control:

• Open Task Scheduler > Create Basic Task.
• Name it something like "Day/Night Wallpaper Switcher".
• Set triggers: Create two separate triggers—one for your desired daytime time, another for nighttime.
• For actions: Choose "Start a program", set "Program/script" to wscript.exe, and add arguments as your VBS file path (e.g., "C:\Scripts\Wallpaper_Switcher.vbs").
• Go to the "General" tab and check Run with highest privileges—this skips UAC prompts during startup/scheduled runs.
• Under "Settings", check "Run task as soon as possible after a scheduled start is missed" to handle cases where your PC was off at the scheduled time.

This method is far more reliable for timed/startup tasks than VBS alone, as it handles permissions and scheduling natively.

内容的提问来源于stack exchange，提问作者Anuja Nimesh