Backup Running WinCC Projects with VSS Shadow Copy

Backing up a live WinCC V7.x project while Runtime is active is a recurring engineering problem. The official WinCC Copy Project tool requires an additional license and cannot be used on every installation. This guide consolidates two VSS-based (Volume Shadow Copy Service) methods that copy locked project databases, archives, and configuration files without interrupting the running HMI/SCADA service, plus a method for scheduling the backup through Windows Task Scheduler.

1. Why Standard File Copy Fails on Live WinCC Projects

A WinCC V7 project is a collection of files under a project directory (default C:\WinCC_Projects\<ProjectName>\) plus an SQL Server database (WinCC V7 uses Microsoft SQL Server 2008 R2 / 2014 depending on version). During Runtime the following handles are open and block the standard Win32 read-share that xcopy or robocopy use:

• CCArchiveConnMon.exe — Connectivity Pack archive connector (when the option is installed).
• CCAlgRt.exe, CCAsmRt.exe — alarm and asset Runtime servers.
• CCProcRt.exe — process value Runtime.
• SQLSERVER.EXE — holds .mdf / .ldf of the project database with an exclusive write lock.

The Windows Volume Shadow Copy Service (VSS) solves this by snapshotting the volume at the NTFS level. VSS-aware tools (VSS requesters) freeze I/O for a few hundred milliseconds, take a consistent snapshot, then release. The user-mode backup then reads from the snapshot, never from the live file handles.

2. Methods Compared

3. Prerequisites

• Administrator account on the WinCC server (VSS requesters must run elevated).
• WinCC V7.0 SP2 or later project on a local NTFS volume.
• Target path with NTFS write permission for the service account running the backup (local folder, UNC share, or USB drive formatted NTFS).
• If using HoboCopy: Microsoft Visual C++ 2010 x86 Redistributable on the operator station if HoboCopy.exe fails to start (MSVCR100.dll missing).
• If scheduling: Windows Task Scheduler service running, account with Log on as batch job right.

4. Method A — HoboCopy (Command-Line)

HoboCopy is a small (under 200 KB) VSS requester originally written by CodePlex contributors and now mirrored on GitHub. It exposes a single HoboCopy.exe with three verbs: backup, replicate, and clone. The replicate verb creates an incremental mirror and is the right choice for project backups.

4.1 Install the Binary

1. Create C:\Tools\Hobocopy\.
2. Extract HoboCopy.exe and HoboCopy.pdb to that directory.
3. (Optional) Install Microsoft Visual C++ 2010 x86 Redistributable if the EXE errors on launch.
4. Verify with: C:\Tools\Hobocopy>HoboCopy.exe — expected output is the syntax help.

4.2 First Full Backup

Open cmd.exe as Administrator and run:

Switches used:

4.3 Incremental Mirror for Daily Backup

After the first successful run, HoboCopy writes a hobocopy.xml journal inside the target root. Subsequent runs become incremental and only touch changed files:

Typical runtime for a 6 GB WinCC project with 50 MB of daily archive deltas: under 90 seconds on local SSD; under 5 minutes on a 1 GbE share.

4.4 Batch File Skeleton

@echo off
set SRC=C:\WinCC_Projects\MyPlant
set DST=\\NAS01\Backup_WinCC\MyPlant
set LOG=C:\Logs\Hobocopy_%date:~-4%%date:~3,2%%date:~0,2%.log

echo --- %date% %time% --- >> %LOG%
"C:\Tools\Hobocopy\HoboCopy.exe" /incremental /r:5 /w:10 %SRC% %DST% >> %LOG% 2>&1
if %ERRORLEVEL% NEQ 0 (
  echo Backup FAILED code %ERRORLEVEL% >> %LOG%
  exit /b %ERRORLEVEL%
)
echo Backup OK >> %LOG%

5. Method B — FreeFileSync (GUI + RealTimeSync)

FreeFileSync wraps the same VSS API as robocopy /Z but exposes a two-pane folder comparison. RealTimeSync is the bundled scheduler.

5.1 Create a Backup Job

1. Install or extract FreeFileSyncPortable.
2. Left pane: browse to C:\WinCC_Projects\MyPlant.
3. Right pane: browse to the destination share.
4. Click Compare — FreeFileSync requests a VSS snapshot, which is why it can read CCArchiveConnMon.exe-locked files in most cases.
5. Synchronize → Mirror.
6. File → Save as Batch Job → Backup_FFS.ffs_batch.

5.2 Known Limitation with Connectivity Pack

If the WinCC server has the Connectivity Pack option installed, the CCArchiveConnMon.exe process holds an exclusive lock on the archive database. FreeFileSync will report file locked by process and skip those files. Two workarounds:

• Use HoboCopy instead (it interacts with VSS at a lower layer and can usually copy these handles).
• Stop only the CCArchiveConnMon Windows service for the duration of the backup: net stop "CCArchiveConnMon", run FFS, net start "CCArchiveConnMon".

5.3 RealTimeSync Schedule

RealTimeSync monitors a folder and triggers the .ffs_batch when the source changes. For a fixed 24-hour schedule, prefer Windows Task Scheduler instead:

6. Scheduling the Backup with Windows Task Scheduler

1. Open taskschd.msc.
2. Create Task (not Basic Task) — name: WinCC_Backup_HoboCopy.
3. Tab General: select Run whether user is logged on or not and Run with highest privileges.
4. Tab Triggers: New → Daily, 02:00, enabled.
5. Tab Actions: New → Action = Start a program, Program = C:\Tools\Hobocopy\Backup.cmd (or the FFS batch + RealTimeSync command).
6. Tab Conditions: uncheck Start only if on AC power on servers; check Start only if the following network connection is available if the target is a UNC share.
7. Tab Settings: If the task fails, restart every 1 minute, up to 3 times; If the running task does not end, force it to stop after 1 hour.
8. Click OK, supply the service account credentials, and tick Do not store password only if the account has a non-expiring password.

7. Verifying the Backup

1. File count parity: robocopy \NAS01\Backup_WinCC\MyPlant C:\Verify /L /E /NJH /NJS /NDL /NP /LOG:verify.log — compare the file count from the backup log to a baseline of the source.
2. Project opens in WinCC Explorer: copy the snapshot to a test station, open WinCC Explorer, activate the project with Runtime stopped. A corrupted *.mdf will throw Database cannot be opened immediately.
3. Archive round-trip: open the Tag Logging editor, switch the archive source to the backup copy, query a known historical tag. Empty values indicate a corrupt .ldf.
4. Checksum: use certutil -hashfile <MDF> SHA256 on both source and snapshot; the hashes must match for files copied while Runtime was idle.

8. Troubleshooting Matrix

9. Retention and Off-Site Copy

Project backups are only as good as their retention. A pragmatic policy for a single-server WinCC plant:

• Hourly incrementals kept for 24 h on a local second disk (fast recovery).
• Daily full mirror (HoboCopy /full) kept for 7 days on a NAS share.
• Weekly full copied off-site (rsync, Robocopy /MIR to a second site, or cloud sync) and kept for 12 months.

Add a scheduled forfiles command to prune:

10. Field-Proven Caveats

• VSS writers on Windows Server 2003 / XP are limited. SQL Server 2005 ships a VSS writer that captures the database in a crash-consistent state. WinCC V7.0.2 was certified on this stack. On Windows Server 2016+ with SQL 2014, the SQL writer is fully application-aware and produces a transactionally consistent backup.
• Avoid running HoboCopy during a WinCC project recompile. The Graphics Designer rewrites picture caches and can hold brief exclusive locks even at the VSS layer. Schedule backups outside the engineering window.
• Antivirus real-time scan of C:\WinCC_Projects will block VSS snapshot creation. Add the project directory to the AV exclusion list on the WinCC server.
• Project paths with spaces must be wrapped in quotes in the HoboCopy command line; UNC targets with embedded spaces are supported but require the /y switch to suppress the overwrite prompt.
• Clustered WinCC / WinCC Redundancy: always back up the preferred server only. The standby server mirrors runtime data via the redundancy DLL, not via the file system, so its project directory is not authoritative.

11. When to Use the Licensed Siemens Tool

Use the official WinCC Copy Project tool (described in SIOS 38493803) when:

• Customer site policy mandates only Siemens-signed executables on the SCADA server.
• You need an MD5/SHA verification report generated by WinCC itself.
• You want the backup to be triggerable from inside the WinCC archive configuration (CCArchiveSrv schedule) rather than Windows Task Scheduler.

Use HoboCopy / FreeFileSync when the licensed tool is not available, when you need a portable install on a service laptop, or when the project is large and a one-shot batch from a UNC share is more practical than the WinCC dialog flow.