Robocopy Cheat Sheet (Windows)

Robocopy (Robust File Copy) is a built-in Windows command-line tool for mirroring, copying, and migrating files. Unlike copy/xcopy, it's resilient (auto-retries), multithreaded, and preserves metadata.

robocopy <Source> <Destination> [files] [options]

Core Syntax

robocopy C:\Source D:\Backup *.* /E

Part	Meaning
`Source`	Folder to copy from (no trailing `\`)
`Destination`	Folder to copy to
`.`	File filter (optional, default = all)
`/E`	Include subdirs, including empty ones

Copy Scope

Flag	Description
`/S`	Copy subdirectories, but not empty ones
`/E`	Copy subdirectories, including empty ones
`/LEV:n`	Only copy top n levels of the tree
`/MIR`	Mirror — `/E` + `/PURGE` (dest becomes identical to source)
`/PURGE`	Delete dest files/dirs that no longer exist in source
`/MOV`	Move files (delete from source after copy)
`/MOVE`	Move files and dirs (delete from source)
`/CREATE`	Create dir tree + zero-length files only (structure scaffold)

⚠️ /MIR deletes. Anything in the destination not in the source gets removed. Always dry-run first.

What Gets Copied (Attributes)

Flag	Copies
`/COPY:DAT`	Data, Attributes, Timestamps (default)
`/COPY:DATSOU`	Adds Security (ACLs), Owner, aUditing
`/COPYALL`	Everything = `/COPY:DATSOU`
`/DCOPY:DAT`	Copy directory timestamps too
`/SEC`	Copy with security (= `/COPY:DATS`)
`/NOCOPY`	Copy nothing (used with `/PURGE` to only clean dest)

Flag letters: D=Data, A=Attributes, T=Timestamps, S=NTFS ACLs, O=Owner info, U=Auditing info.

Performance (Advanced)

Flag	Effect
`/MT[:n]`	Multithreaded copy, n = 1–128 threads (default 8). Huge speedup on many small files
`/J`	Unbuffered I/O — best for large files (VMs, ISOs, DBs)
`/NOOFFLOAD`	Disable Windows copy offload (for some SAN/NAS edge cases)
`/COMPRESS`	SMB compression during transfer (Win11/Server 2022+)
`/IPG:n`	Inter-packet gap (ms) — throttle bandwidth on slow links

robocopy \\src\share D:\local /E /MT:32 /J

Tip: /MT and logging — multithreaded output interleaves, so always pair with /LOG for clean records.

Selecting / Filtering Files

Flag	Meaning
`/XF file [file]...`	eXclude Files (supports wildcards: `*.tmp`)
`/XD dir [dir]...`	eXclude Directories (e.g. `node_modules`)
`/XO`	Exclude older — skip src files older than dest
`/XN`	Exclude newer
`/XC`	Exclude changed
`/XX`	Exclude extra (dest-only) files — protects them from `/MIR`
`/XL`	Exclude lonely (src-only) files
`/IS`	Include same — recopy identical files
`/IT`	Include tweaked files
`/MAX:n` / `/MIN:n`	Max/min file size in bytes
`/MAXAGE:n` / `/MINAGE:n`	Max/min file age (n days, or `YYYYMMDD`)
`/MAXLAD` / `/MINLAD`	Filter by last access date
`/A`	Copy only files with Archive attribute set
`/M`	Same as `/A` but clears the Archive bit (incremental backups)
`/IA:RASHCNETO` / `/XA:...`	Include/exclude by attribute

Resilience & Retry

Flag	Description
`/R:n`	Retry count on failed copies (default 1 million — set low!)
`/W:n`	Wait seconds between retries (default 30)
`/Z`	Restartable mode (resume interrupted large copies)
`/B`	Backup mode — uses backup privileges to bypass ACLs
`/ZB`	Try restartable; fall back to backup mode (best for migrations)
`/TBD`	Wait for share names to be defined
`/EFSRAW`	Copy encrypted (EFS) files in raw mode

🔑 Always set /R:3 /W:5. Defaults (/R:1000000 /W:30) can hang for weeks on a single locked file.

Logging & Reporting

Flag	Description
`/L`	List only — dry run, copies nothing (test `/MIR` here!)
`/LOG:file`	Write log (overwrite)
`/LOG+:file`	Write log (append)
`/UNILOG:file`	Unicode log
`/TEE`	Output to console and log
`/NP`	No progress % (cleaner logs)
`/NDL`	No directory list
`/NFL`	No file list
`/NS`	No size info
`/NC`	No file class
`/V`	Verbose (shows skipped files)
`/ETA`	Show estimated completion time
`/BYTES`	Sizes in bytes
`/X`	Report all extra files (not just selected)

Clean-log combo: /NP /NDL /NFL /NC /NS then check the summary table only.

Common Recipes

Dry-run a mirror (do this first, always):

robocopy C:\Data D:\Backup /MIR /L /NP

True mirror with safe retries + log:

robocopy C:\Data D:\Backup /MIR /R:3 /W:5 /MT:16 /LOG:C:\logs\backup.log /TEE /NP

Server migration preserving all permissions:

robocopy \\OLD\Share \\NEW\Share /E /ZB /COPYALL /DCOPY:DAT /R:2 /W:5 /MT:32 /LOG:migrate.log

Incremental backup (only changed files, clears archive bit):

robocopy C:\Source D:\Dest /M /E /R:2 /W:5

Move files older than 30 days to archive:

robocopy C:\Active D:\Archive /MOV /MINAGE:30 /E /R:1 /W:1

Copy only large files (>100 MB), unbuffered:

robocopy C:\VMs D:\VMs *.vhdx /J /MIN:104857600 /R:2 /W:5

Sync but protect destination-only files from deletion:

robocopy C:\Src D:\Dst /E /XX /R:2 /W:5

Exit Codes (Advanced — Crucial for Scripting)

Robocopy returns a bitmask, not the usual 0=success. Anything < 8 is success.

Code	Meaning
`0`	No change — source & dest identical
`1`	Files copied successfully
`2`	Extra files/dirs in dest (not in source)
`3`	`1+2` — copied + extras present
`4`	Mismatched files/dirs
`8`	Some files failed to copy (real error)
`16`	Fatal error — no copy occurred

Treat as failure only if code ≥ 8. In batch/PowerShell:

robocopy C:\Src D:\Dst /MIR /R:3 /W:5
if ($LASTEXITCODE -ge 8) { Write-Error "Robocopy failed: $LASTEXITCODE" }
else { Write-Host "OK ($LASTEXITCODE)" }

:: Batch equivalent
robocopy C:\Src D:\Dst /MIR
if %ERRORLEVEL% GEQ 8 echo FAILED & exit /b 1
exit /b 0

⚠️ In CI/scheduled tasks, a naive if %ERRORLEVEL% NEQ 0 flags normal successful copies as failures. Always compare with GEQ 8.

Advanced Concepts & Gotchas

Job files: Save complex command sets and reuse them.

robocopy /SAVE:mybackup    :: writes mybackup.RCJ
robocopy /JOB:mybackup     :: run it
robocopy /JOB:mybackup /QUIT  :: parse & quit (validate without running)

Long paths (>260 chars): Robocopy supports them natively — one of its biggest advantages over Explorer/copy.
/MIR vs /E /PURGE: identical. The danger is the PURGE half — if you point Source at the wrong/empty folder, you wipe the destination. Dry-run with /L guards against this.
/MT + /Z conflict: Restartable mode (/Z) is significantly slower and partially negated by multithreading — pick /MT for many small files, /Z (or /J) for big files over flaky links.
Timestamps drift: Without /DCOPY:T (or /DCOPY:DAT), folder timestamps reset to "now." Add it for true fidelity.
Mirroring junctions/symlinks: Robocopy follows them by default and can cause infinite loops. Use /XJ to exclude junction points; /SL to copy symlinks as links rather than targets.
Permissions need elevation: /COPYALL, /B, /ZB, and /SEC typically require an admin prompt; otherwise ACL/owner copy silently degrades.
Bandwidth throttling: No native rate limit, but /IPG:n (inter-packet gap in ms) approximates one for WAN copies.
Empty-dir behavior: /S skips empty folders; /E keeps them. Mirroring a structure-only tree needs /E (or /CREATE).

Quick "Safe Defaults" Template

robocopy "SOURCE" "DEST" /E /R:3 /W:5 /MT:16 /COPY:DAT /DCOPY:DAT /XJ ^
  /LOG:"C:\logs\robocopy_%date:~-4%%date:~3,2%%date:~0,2%.log" /TEE /NP

Drop /E→/MIR only after you've verified with /L.

Reference cheat sheet — Windows built-in robocopy. Run robocopy /? for the full inline help.