Prerequisites

• Windows 10 or Windows 11 with admin rights.

• PowerShell (built in).

• Enough disk space to initially create the ZIP archive.

Files & variables (example)

Steps

1. Create Archive Folder

   • Create D:\Archive\OldFiles (or your target).

   • Ensure you have write permissions.

2. Save the PowerShell script (e.g., C:\Scripts\CompressOldFiles.ps1):

   param(
[string]$SourceFolder = "C:\Users\Public\LargeFiles",
[string]$ArchiveFolder = "D:\Archive\OldFiles",
[int]$DaysThreshold = 90
)
$DateCutoff = (Get-Date).AddDays(-$DaysThreshold)
$Files = Get-ChildItem -Path $SourceFolder -Recurse | Where-Object { !$_.PSIsContainer -and $_.LastAccessTime -lt $DateCutoff }
if ($Files.Count -eq 0) { exit }
$ZipFileName = "Archive_$((Get-Date).ToString('yyyyMMdd')).zip"
$TempZipPath = Join-Path $env:TEMP $ZipFileName
Compress-Archive -Path $Files.FullName -DestinationPath $TempZipPath
Move-Item -Path $TempZipPath -Destination (Join-Path $ArchiveFolder $ZipFileName)
# Optionally delete originals:
# foreach ($f in $Files) { Remove-Item $f.FullName }


3. Open Task Scheduler

   • Create a new task → Give it a name like “Compress Old Files”.

   • Trigger: daily (choose a time when PC is on).

   • Action: Start a program → powershell.exe

     • Add arguments: -File "C:\Scripts\CompressOldFiles.ps1" -SourceFolder "C:\Users\Public\LargeFiles" -ArchiveFolder "D:\Archive\OldFiles" -DaysThreshold 90

   • Conditions: maybe only if idle or if on AC power.

4. Test it

   • Manually run the task and check you get a ZIP file in the Archive folder.

   • Verify disk space is freed.

   • Adjust DaysThreshold if you want older/newer files.

Troubleshooting & notes

• If you get permission errors, check that your user account or the scheduled task’s user has read access to the source and write to archive.

• Large archives can take time — monitor task duration.

• Consider how long you want to keep archives. You might add a cleanup step (e.g., delete archives older than X days).

• This doesn’t replace a proper backup: archived files are still on disk (or same machine) so risk remains if drive fails.