Random Wallpaper (Windows)

A PowerShell script that sets a random desktop wallpaper from a folder. It supports a Windows system tray icon with a right‑click menu to manually change the wallpaper, configure the schedule (minutes), choose the image folder, toggle subfolder inclusion, pick style, and enable/disable scheduling. Settings persist under your profile.

Features

• System tray app (Windows Forms)
  • Change now
  • Set folder… (browse)
  • Set interval (minutes)…
  • Include subfolders (toggle)
  • Style: Fill, Fit, Stretch, Center, Tile, Span
  • Scheduling enabled (toggle)
  • Start at logon (toggle via Startup shortcut)
  • Open images folder
  • Exit
• Custom tray icon
  • Uses tray.ico (or icon.ico) if present next to the script
  • If none is present, the script auto-generates a multi-resolution tray.ico (16, 24, 32, 48, 64, 128, 256) with an image‑themed design (mountain + sun)
  • The tray and Startup shortcut will use the appropriate size for your DPI
• One‑off or continuous (non‑tray) modes
• Optional Scheduled Task to run continuously at user logon
• Supported images: jpg, jpeg, png, bmp

Requirements

• Windows 10/11
• PowerShell 7+ (tested with 7.5.3), executable pwsh
• .NET Windows Desktop assemblies (System.Windows.Forms/System.Drawing) – present by default on Windows desktops

Files

• rand_wallpaper.ps1 – the main script
• tray.ico – auto-generated on first run if missing; place your own to override (or use icon.ico)
• Config: %AppData%\RandomWallpaper\config.json (created/updated by tray mode)

Quick start

Run the tray app (recommended):

pwsh -NoProfile -ExecutionPolicy Bypass -File .\rand_wallpaper.ps1 -Tray

Then right‑click the tray icon to configure your folder, schedule, recurse, and style. Double‑click the tray icon or select “Change now” to immediately set a random wallpaper.

Autostart at sign‑in (Startup shortcut)

Install a Startup shortcut that launches the tray app at logon:

pwsh -NoProfile -ExecutionPolicy Bypass -File .\rand_wallpaper.ps1 -InstallStartup

Remove it:

pwsh -NoProfile -ExecutionPolicy Bypass -File .\rand_wallpaper.ps1 -UninstallStartup

You can also toggle “Start at logon” directly from the tray menu.

Notes:

• The shortcut is created in your user Startup folder with target pwsh.exe and arguments -NoProfile -ExecutionPolicy Bypass -File "<script>" -Tray.
• The shortcut icon uses tray.ico or icon.ico if available; otherwise a system icon.

Scheduled Task (optional, non‑tray)

Create a Scheduled Task to start the script at logon and run continuously (the script itself loops on your selected interval):

pwsh -NoProfile -ExecutionPolicy Bypass -File .\rand_wallpaper.ps1 -InstallBackground -ImageFolder "C:\Wallpapers" -IntervalMinutes 30 -Style Fill -Recurse -TaskName RandomWallpaper

Remove the task:

pwsh -NoProfile -ExecutionPolicy Bypass -File .\rand_wallpaper.ps1 -UninstallBackground -TaskName RandomWallpaper

Notes:

• Uninstall may prompt for elevation.
• The task is registered for the current user (Interactive, Limited).

One‑off change

Set one random wallpaper and exit:

pwsh -NoProfile -ExecutionPolicy Bypass -File .\rand_wallpaper.ps1 -Once

Continuous (non‑tray) session

Run in the foreground continuously, changing every N minutes:

pwsh -NoProfile -ExecutionPolicy Bypass -File .\rand_wallpaper.ps1 -ImageFolder "C:\Wallpapers" -IntervalMinutes 30 -Style Fill -Recurse

Press Ctrl+C to stop.

Parameters (CLI)

• -ImageFolder <path>
  • Folder containing images. Default prefers %USERPROFILE%\Pictures\Wallpapers (or Known Folders variant), otherwise falls back to %USERPROFILE%\Pictures and %USERPROFILE%\wallpapers.
• -IntervalMinutes <int>
  • Minutes between changes. Default: 240. Minimum enforced: 1.
• -Style <Fill|Fit|Stretch|Center|Tile|Span>
  • Wallpaper style. Default: Stretch.
• -Recurse (switch)
  • Include images from subfolders. Default: true unless explicitly set otherwise.
• -Once (switch)
  • Set a random wallpaper once and exit.
• -Tray (switch)
  • Start the tray app (Windows Forms message loop). The tray has its own scheduler/timer and persists settings.
• -InstallStartup / -UninstallStartup (switch)
  • Install/remove a Startup shortcut that launches tray mode at sign‑in.
• -InstallBackground / -UninstallBackground (switch)
  • Install/remove a Scheduled Task that starts the script at logon and runs continuously.
• -TaskName <string>
  • Name for the Scheduled Task. Default: RandomWallpaper.

Tray mode details

• Persisted settings: %AppData%\RandomWallpaper\config.json
  • ImageFolder: string
  • IntervalMinutes: number (minutes)
  • Style: one of Fill|Fit|Stretch|Center|Tile|Span
  • Recurse: boolean
  • ScheduleEnabled: boolean (enables the tray timer)
• Timer/scheduler is internal to the tray app and can be toggled via the menu (“Scheduling enabled”).
• Double‑click the tray icon = “Change now”.
• Icon:
  • Provide tray.ico (or icon.ico) next to the script for a custom icon. A 16×16 (and/or multi‑resolution) ICO is recommended.
  • If not present, a small image‑style icon is drawn programmatically.
• If you don’t see the tray icon, check the hidden icons overflow menu in the Windows taskbar.

Styles mapping

The script sets registry values equivalent to Windows styles:

• Fill → WallpaperStyle=10, TileWallpaper=0
• Fit → WallpaperStyle=6, TileWallpaper=0
• Stretch → WallpaperStyle=2, TileWallpaper=0
• Center → WallpaperStyle=0, TileWallpaper=0
• Tile → WallpaperStyle=0, TileWallpaper=1
• Span → WallpaperStyle=22, TileWallpaper=0 (multi‑monitor spanning)

Supported image formats

• jpg, jpeg, png, bmp

Troubleshooting

• “No images found”: Check the selected folder and whether “Include subfolders” is set appropriately.
• Execution policy blocks script: use the examples here which pass -ExecutionPolicy Bypass per‑invocation, or Unblock-File .\\rand_wallpaper.ps1 as needed.
• Tray icon not visible: It may be hidden in the taskbar overflow. Drag it into the visible area if desired.
• Multi‑monitor behavior: Use Span style to span a single image across displays; other styles apply per‑monitor.
• OneDrive Pictures redirection: The script resolves the Windows Known Folder for Pictures to find your default Wallpapers folder if present.
• Error “SystemParametersInfo failed…”: Ensure the image path is accessible and the file type is supported.

Uninstall / Cleanup

• Remove Startup shortcut:

  pwsh -NoProfile -ExecutionPolicy Bypass -File .\rand_wallpaper.ps1 -UninstallStartup

• Remove Scheduled Task:

  pwsh -NoProfile -ExecutionPolicy Bypass -File .\rand_wallpaper.ps1 -UninstallBackground -TaskName RandomWallpaper

• Remove tray settings: delete %AppData%\RandomWallpaper\config.json (optional). Close the tray app via its “Exit” menu.

License

Not specified.