ExtractToDirectory gives error “Extracting Zip entry would hvae resulted in a file outside the specified destination directory”

Question

I'm working on a script to extract all zips in my downloads folder to a directory on my desktop. I got it working fine for my purposes but there's a single .zip file I had tried that is giving me issues.

When trying to ExtractToDirectory, it returns that there are 2 arguments and that "Extracting to Zip entry would hvae resulted in a file outside the specified destination directory" I'm able to use WinZip as well as file explorer's Extract All to unzip this .zip correctly. I'm at a loss of what the issue might be.

#Script to Unzip .zip files in downloads folder.

#$src = file you're unzipping, $dest = destination for contents

$src = 'C:\Users\' + $env:USERNAME + '\Downloads\'
$dest = 'C:\Users\' + $env:USERNAME + '\Desktop\Zips\'

Function UnZipper($src, $dest)
{
    Add-Type -AssemblyName System.IO.Compression.FileSystem
    #specifies zip files in directory
    $zps = Get-ChildItem $src -Filter *.zip

    #unpacks each zip in directory to destination folder
    foreach ($zp IN $zps)
    {
        #Sets File Path of original zip
        $Zips = ($src + $zp)
        #Sets destination of zip. Creates folder if it does not exist.
        $NewFolder = $dest + $zp
        $NewFolder = $NewFolder.TrimEnd(".zip")
        #Checks if file already exists (has been unzipped)
        $FileExists = Test-Path $NewFolder
        If ($FileExists -eq $false)
        {
        Write-Host 'UnZipping -'$zp
        [System.IO.Compression.ZipFile]::ExtractToDirectory($Zips, $NewFolder)
        }
    }
}

UnZipper -src $src -dest $dest
Write-Host "Your files have been Un-Zipped!"
Write-Host "Press the enter key to exit and open your file(s)" -ForegroundColor Green
Read-Host
explorer $dest

Ultimately if it's a problem with the specific zip that cannot be fixed, that's fine with me. I'm just trying to figure out why it works with WinZip but not PowerShell.

Answer 1

$zps = Get-ChildItem $src -Filter *.zip -File produces an array of FileInfo objects and you should not treat them as simple file path strings as you do in the foreach loop.

Better use the Join-Path cmdlet to construct paths where needed:

Below a re-write of your function

function UnZipper {
    [CmdletBinding()]
    param(
        [Parameter(Mandatory = $true, Position = 0)]
        [string]$src,

        [Parameter(Mandatory = $true, Position = 1)]
        [string]$dest
    )
    Add-Type -AssemblyName System.IO.Compression.FileSystem

    # get an array of FileInfo objects for zip files in the $src directory and loop through
    Get-ChildItem $src -Filter *.zip -File | ForEach-Object {
        # unpacks each zip in directory to destination folder
        # the automatic variable '$_' here represents a single FileInfo object, each file at a time

        # Get the destination folder for the zip file. Create the folder if it does not exist.
        $destination = Join-Path -Path $dest -ChildPath $_.BaseName  # $_.BaseName does not include the extension

        # Check if the folder already exists
        if (!(Test-Path $destination -PathType Container)) {
            # create the destination folder
            New-Item -Path $destination -ItemType Directory -Force | Out-Null

            # unzip the file
            Write-Host "UnZipping - $($_.FullName)"
            [System.IO.Compression.ZipFile]::ExtractToDirectory($_.FullName, $destination)
        }
        else {
            Write-Host "Folder '$destination' already exists. File skipped."
        }
    }
}