Extract files and folders from SharePoint 2013 document library to local folder

Hi @john john :
Based on my research and testing, please try to use the following PowerShell script to download files and folders from the document library to a local folder:

 Add-PSSnapin Microsoft.Sharepoint.Powershell  
 $SiteURL = "http://sp/xxx"  
 $LibraryName ="library"  
 $DownloadPath ="C:\library"  
 Function Download-SPFolder($SPFolderURL, $DownloadPath)  
 {  
      Try {  
          $SPFolder = $web.GetFolder($SPFolderURL)  
          Write-host $SPFolder  
          $DownloadPath = Join-Path $DownloadPath $SPFolder.Name   
          If (!(Test-Path -path $DownloadPath))  
          {     
              $LocalFolder = New-Item $DownloadPath -type directory  
          }  
          ForEach ($File in $SPFolder.Files)  
          {  
              #Download the file  
              $Data = $File.OpenBinary()  
              $FilePath= Join-Path $DownloadPath $File.Name  
              [System.IO.File]::WriteAllBytes($FilePath, $data)  
              Write-host -f Green "`tDownloaded the File:"$File.ServerRelativeURL          
          }  
          ForEach ($SubFolder in $SPFolder.SubFolders)  
          {  
              If($SubFolder.Name -ne "Forms")  
              {  
                  #Call the function Recursively  
                  Download-SPFolder $SubFolder $DownloadPath  
              }  
          }  
      }  
      Catch {  
          Write-host -f Red "Error Downloading Document Library:" $_.Exception.Message  
      }   
 }  
 #Main Function  
 Function Download-SPDocumentLibrary($SiteURL, $LibraryName, $DownloadPath)  
 {  
      Try {  
          #Get the  Web  
          $Web = Get-SPWeb $SiteURL  
          #Delete any existing files and folders in the download location  
          If (Test-Path $DownloadPath) {Get-ChildItem -Path $DownloadPath -Recurse| ForEach-object {Remove-item -Recurse -path $_.FullName }}  
          #Get the document Library to Download  
          $Library = $Web.Lists[$LibraryName]  
          Write-host -f magenta "Downloading Document Library:" $Library.Title  
          #Call the function to download the document library  
          Download-SPFolder -SPFolderURL $Library.RootFolder.Url -DownloadPath $DownloadPath  
          Write-host -f Green "*** Download Completed  ***"  
      }  
      Catch {  
          Write-host -f Red "Error Downloading Document Library:" $_.Exception.Message  
      }   
 }  
 Download-SPDocumentLibrary $SiteURL $LibraryName $DownloadPath  

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