How to Use Robocopy in Windows: Backup and File Sync Guide

Robocopy (Robust File Copy) is built into Windows and outperforms standard copy in every way — it resumes interrupted transfers, preserves timestamps and handles network errors gracefully.

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Basic Syntax

robocopy <source> <destination> [files] [options]

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Common Use Cases

Mirror a folder (exact copy, delete extras):

robocopy "C:\Source" "D:\Backup" /MIR /R:3 /W:5

Copy new and changed files only:

robocopy "C:\Source" "D:\Backup" /E /XO /R:3 /W:5

Copy specific file types:

robocopy "C:\Documents" "D:\DocBackup" *.pdf *.docx *.xlsx /E /R:3

Network copy with progress:

robocopy "C:\Source" "\\Server\Share\Backup" /E /R:3 /W:10 /NP /LOG:C:\robocopy.log

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Key Options Explained

Option	What it does
/MIR	Mirror — copies new/changed AND deletes files removed from source
/E	Copy all subdirectories including empty ones
/XO	Exclude Older — skip files that are newer in destination
/R:3	Retry 3 times on failure
/W:5	Wait 5 seconds between retries
/LOG:file	Save output to log file
/NP	No progress — cleaner output
/COPYALL	Copy all file attributes including permissions
/PURGE	Delete destination files not in source (without full mirror)
/MT:8	Multi-threaded copy with 8 threads (faster for many small files)

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Scheduled Backup via Task Scheduler

# Create daily backup task at 2 AM
$action  = New-ScheduledTaskAction -Execute "robocopy.exe" `
  -Argument '"C:\Documents" "D:\Backup\Documents" /MIR /R:3 /W:5 /LOG:C:\Logs\backup.log'
$trigger = New-ScheduledTaskTrigger -Daily -At "2:00AM"
Register-ScheduledTask -TaskName "DailyDocBackup" `
  -Action $action -Trigger $trigger -RunLevel Highest

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Sync Two Folders

REM One-way sync: Source → Destination
robocopy "C:\Work" "D:\WorkSync" /MIR /R:2 /W:3

REM Copy only files modified in the last 7 days
robocopy "C:\Source" "D:\Recent" /E /MAXAGE:7 /R:2 /W:3

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Robocopy Exit Codes

# Run robocopy and check exit code
$result = (Start-Process robocopy -ArgumentList '"C:\Src" "D:\Dst" /E' -Wait -PassThru).ExitCode
switch ($result) {
  0 { "No files copied — destination already up to date" }
  1 { "Files copied successfully" }
  2 { "Extra files in destination (would be deleted with /PURGE)" }
  4 { "Some mismatched files — check log" }
  8 { "Some files failed to copy — check log" }
  16 { "Fatal error — no files copied" }
  default { "Code $result — check robocopy log" }
}

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Useful Combinations

REM Full backup preserving permissions and timestamps
robocopy "C:\Source" "D:\FullBackup" /COPYALL /MIR /R:5 /W:10 /LOG:C:\backup.log

REM Fast large file copy (multi-threaded, no retry spam)
robocopy "C:\LargeFiles" "D:\Target" /E /MT:16 /R:1 /W:1

REM Dry run — show what WOULD be copied without actually copying
robocopy "C:\Source" "D:\Dest" /E /L /NP

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Summary

Use /MIR for exact mirror backups, /E /XO for incremental sync. Always add /R:3 /W:5 to handle temporary failures. Use /LOG: to save output for review. Schedule with Task Scheduler for automated backups. Exit code 1 = success, anything ≥ 8 = investigate the log.

Frequently Asked Questions

Is Robocopy better than xcopy?

Yes. Robocopy handles retries, multi-threading, preserves all NTFS attributes, and has better error reporting. xcopy is obsolete — use Robocopy instead.

Does /MIR delete files from destination?

Yes. /MIR makes the destination an exact mirror — files deleted from source will be deleted from destination on the next run. Use /E /XO if you want a one-way copy without deletions.

Can Robocopy copy open files?

Not directly. For open files (like a live database), use Volume Shadow Copy: robocopy \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy1\ "D:\Backup" after creating a VSS snapshot.