Automate nightly backups on Windows

Reliable backups should run even when nobody remembers to start them. This guide explains how to schedule nightly backups with Windows Task Scheduler and Robocopy, using tools already included with Windows 10 and Windows 11. The setup copies selected folders to another disk or network location, writes a log and gives Task Scheduler a clear success or failure result.

Robocopy is built for Windows file systems and handles large directory trees more efficiently than basic Copy and Paste. Task Scheduler supplies the clock, execution account and unattended trigger. Together they suit routine backups on a desktop or small-office server, although a copied folder alone does not protect against every disk, theft or ransomware event.

A second internal partition can prevent accidental deletion, but it will not survive failure of the same disk or drive. An external drive kept disconnected after the copy adds useful protection, while a network-attached storage device can provide an always-available destination. The strongest arrangement keeps copies on separate storage and in another location.

Australian timing deserves attention. Sydney, Melbourne, Adelaide and Hobart move between AEDT and AEST, while Brisbane stays on AEST and Perth stays on AWST. During the October clock jump, 02:30 does not exist in the eastern states, and April’s backward change repeats part of the morning. Set the task for 04:00 local time to avoid those ambiguous windows.

Choose what to copy and where it goes

Start by listing the folders that would be painful to replace, then exclude volatile data such as browser caches and temporary downloads. Include active documents, design projects, client files, virtual-machine disks that are safely shut down, and local exports of accounting data needed for BAS and GST preparation. For an Australian sole trader, receipts and accounting exports can be irreplaceable even when the main records live in an online accounting system.

Next, choose a destination based on the failure it is meant to cover. A different internal disk handles accidental deletion; a USB disk handles an internal disk failure if it is kept safe; a NAS is useful when several devices need one destination. For a home office or small Australian business, place the destination on storage that is not part of the daily working set, and document its drive letter or UNC path.

Set a retention policy before the first run. Robocopy can update the same destination efficiently, but repeated copies into one folder may eventually preserve clutter or old files that you no longer need. Versioned snapshots, a dated weekly destination or a backup product with retention controls can keep several recovery points. Decide who checks them and how quickly a damaged file must be restored.

Prepare folders, accounts and permissions

Create the destination and log directories before configuring the task. A practical layout is E:\Backups\Business Records with logs in E:\BackupLogs. Keep the destination outside the source tree; otherwise Robocopy may repeatedly copy a backup into another backup folder. Make sure the destination has enough free space for the full initial copy, not merely the files added each night.

The scheduled task needs an account that can read the source and create, modify and write files in the destination. Avoid relying on a mapped network drive such as Z: because interactive drive mappings may be unavailable when Task Scheduler runs without a logged-in user. Use a UNC path such as \\vault\Backups\Business Records for a NAS, or use a local Windows volume. For removable media, confirm that the drive letter remains consistent or mount the volume at a fixed path.

Stable power and closed applications also matter. Australian mains is nominally 230 volts at 50 Hz, so select surge protection or a UPS intended for local mains and Australian-market warranty support. Robocopy is a file-level tool: close Outlook, design applications and databases before the run, or exclude files that applications keep open. A VSS-aware backup tool is safer for continuously used server data.

Build a repeatable Robocopy command

Save the following as C:\Scripts\NightlyBackup.cmd, replacing the example source and destination with your own paths. The script records the Robocopy exit code and returns zero to Task Scheduler only when the copy succeeds.

@echo off
set "SOURCE=D:\Business Records"
set "DEST=E:\Backups\Business Records"
set "LOGDIR=E:\BackupLogs"

if not exist "%LOGDIR%" mkdir "%LOGDIR%"

"%SystemRoot%\System32\robocopy.exe" "%SOURCE%" "%DEST%" /E /COPY:DAT /DCOPY:DAT /XJ /R:2 /W:10 /MT:8 /NP /LOG+:"%LOGDIR%\Nightly.log"
set "RC=%ERRORLEVEL%"

if errorlevel 8 (
    echo %date% %time% Backup failed with Robocopy code %RC%.>>"%LOGDIR%\Nightly.log"
    exit /b 1
)

exit /b 0

The /E switch copies existing subdirectories, including empty ones. /COPY:DAT and /DCOPY:DAT preserve data, attributes and timestamps without taking ownership of the destination. /XJ skips junction points that can create unnecessary loops. /R:2 and /W:10 retry failed files twice, ten seconds apart, while /MT:8 allows eight worker threads for faster copying.

The script deliberately omits /MIR. Although it creates an exact mirror, it also deletes destination files that no longer exist in the source and could erase protection against an accidental source deletion. Robocopy exit codes from zero through seven indicate successful completion, including cases where files were copied; eight and above indicate failure. The wrapper converts Robocopy’s result into a clear Task Scheduler outcome.

For a NAS, replace the destination with its UNC path while retaining the quotation marks. If the server uses a different timestamp format, such as some exFAT or SMB configurations, add /FFT. Test the command manually before scheduling it so that path, permission and file-lock errors can be corrected without waiting overnight.

Configure the scheduled task in Task Scheduler

Open Task Scheduler by pressing Windows+R, entering taskschd.msc and selecting the Task Scheduler Library. Choose Create Task rather than the basic version. On the General tab, give the task a descriptive name, select Run whether user is logged on or not, and choose the account that owns the source files. If access is denied, confirm that this account has both read and write permissions and can run a batch job.

Create a daily trigger at 04:00 local time and leave it enabled. On the Actions tab, select Start a program. Enter C:\Windows\System32\cmd.exe as the program and /d /c "C:\Scripts\NightlyBackup.cmd" as the arguments. Set Start in to C:\Scripts, then save the task. The script path must remain readable by the selected execution account.

In Settings, allow the task to run on demand, retry if it fails and run as soon as possible after a missed start. Set a maximum runtime long enough for the largest expected copy. Conditions can prevent a laptop task from starting on battery, but desktop and server systems should be configured to continue during a power interruption. Task Scheduler follows the computer’s local clock and handles daylight-saving changes, yet reviewing the task history after both Australian clock-change dates remains worthwhile.

Test the backup and verify restoration

Run the task manually with Run in Task Scheduler and watch its progress in the History tab. Open E:\BackupLogs\Nightly.log and check for copied, skipped and failed files. A successful task should show Last Run Result as 0, because the wrapper converts Robocopy’s successful codes into a zero exit status. A non-zero result requires investigation rather than an assumption that no files were copied.

Compare several source and destination files, including one from a nested folder and one with spaces in its filename. Confirm that the copied versions open correctly and retain useful timestamps. Then restore a sample document into a temporary folder and open it from there. Restoring into a separate test location proves that the data is usable without overwriting the only good copy.

Repeat the test after changing the source, such as editing a document and creating a new folder. If files remain locked during the run, revise the scope or close the application before scheduling. Keep a second recovery method for databases or mailboxes that require application-consistent snapshots, since a successful Robocopy exit does not guarantee that every open file was captured coherently.

Keep copies protected and respond to failures

Review the backup regularly rather than waiting for a failure. Confirm that the log is growing, the destination has sufficient capacity and the copied files remain accessible. Keep at least one copy on separate storage and another away from the premises. If backups contain client or employee information, organisations covered by Australia’s Privacy Act 1988 should also follow OAIC guidance about access, retention and secure disposal.

Make sure alerts reach someone responsible for the computer. Notification is needed when the task reports a non-zero result, the log stops updating or a NAS becomes unreachable. Typical causes include a disconnected external drive, changed network credentials, insufficient space or ransomware locking source files. Test the response procedure, including reconnecting storage and rerunning the task, so recovery does not depend on improvising under pressure.

Build the backup routine now: create the source, destination and script, run one manual copy, restore a sample file and activate the 04:00 schedule. Check the log after the first three nightly runs, and treat a missing or incomplete copy as a failed backup until every required folder has been verified.