Resolving WinCC Flexible SQL Desktop Engine Installation Failures

Problem Overview

WinCC Flexible 2007 and 2008 install routines deploy the Microsoft SQL Server 2000 Desktop Engine (MSDE 2000, version 8.0) or, in the WinCC Flexible 2008 SP5 update, SQL Server 2005 Express SP3 as the back-end repository for project libraries, recipe archives, alarm logs, audit trails, and runtime data sets. When the embedded SQL setup fails at the start of the WinCC Flexible installation sequence, the entire installer halts and reports a generic "could not be installed" message with no native log capture visible to the operator. This failure pattern appears across the entire WinCC Flexible product line (Compact, Standard, Advanced editions) and is independent of HMI panel type, project size, or runtime target.

The visible symptom is one of the following error strings emitted either by the Windows Installer host or by the embedded MSDE 2000 setup runtime:

• Setup failed to install the SQL Server Database Engine
• The instance name specified is invalid
• A previous installation of MSDE has been detected. Setup will exit.
• MSDE installation failed - see setup log for details
• SQL Server Setup cannot continue because the instance name is invalid or already in use
• Internal Error 2711 with an MSI rollback loop
• Setup failed to configure the server. Refer to the SQL Server setup log for details.

Because WinCC Flexible bundles its own MSDE payload, the Siemens Setup wrapper never exposes the underlying SQL Server error log to the GUI, leaving the technician with a black-box failure. Root causes cluster into five families: incomplete uninstallation of a prior SQL Server 2000/2005 instance, antivirus or file-system filter interception of the SQL setup binary, missing Microsoft Message Queuing (MSMQ) component required by SQL Server services, Microsoft Office 2003/2007 MSI installer collision, and insufficient local-administrator privileges for the installing account.

Affected Products and Versions

Root Cause Matrix

Pre-Installation Checklist

1. Log in with a local administrator account (not a domain user with admin rights via UAC token only). Confirm via net localgroup administrators from an elevated command prompt.
2. Disable all third-party antivirus, anti-malware, and host-based intrusion prevention software. Configure Windows Defender real-time protection to off through Group Policy or the Security Center.
3. Disable Windows Firewall or add an inbound allow rule for TCP 1433 (SQL Server default instance) and the SQL Server Browser service on UDP 1434.
4. Remove Microsoft Office 2003 and 2007 if installed. Office 2003 MSI components share file identity hashes with the SQL Server 2000 MSDE installer and trigger MSI rollback chains.
5. Stop all running SQL services: net stop MSSQLSERVER, net stop SQLSERVERAGENT, net stop MSSQLServerADHelper, net stop SQLBrowser.
6. Verify MSMQ is installed: Control Panel → Add/Remove Programs → Add/Remove Windows Components → check "Message Queuing Server".
7. Confirm at least 1.5 GB free disk space on the system drive for the WinCC Flexible install plus the embedded SQL payload plus a working buffer.
8. Insert the WinCC Flexible installation DVD or mount the ISO file. Note the drive letter, e.g. D:.
9. Verify the OS architecture matches the WinCC Flexible media: 32-bit media installs only on 32-bit hosts; WinCC Flexible 2008 SP5 64-bit SQL 2005 Express payload requires a 64-bit OS image.
10. Back up any existing project archives under %USERPROFILE%\Siemens\WinCC Flexible before modifying the registry or removing Office.

Resolution Procedure

Step 1 - Remove Residual SQL Server Instances

The "instance name specified is invalid" error is the most common symptom and almost always indicates a leftover SQL Server registration from a previously removed SQL Server 2000, MSDE, or SQL Server 2005 Express installation. The MSDE installer cannot reuse the registered instance name and cannot overwrite the existing entry, so the embedded setup aborts before any binaries are written.

1. Open the registry editor (regedit.exe) as administrator.
2. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server.
3. Delete subkeys Instance Names, MSSQLServer, MSSQLServerADHelper, and any subkey beginning with WINCCFLEXIBLE.
4. On 64-bit hosts also check HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Microsoft SQL Server and remove the same subkeys.
5. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall and delete any SQL Server or MSDE GUID entries (look for DisplayName containing "Microsoft SQL Server" or "MSDE").
6. Delete the install directories: C:\Program Files\Microsoft SQL Server\MSSQL, C:\MSSQL7, C:\MSSQL, and any folder containing sqlservr.exe.
7. Delete the data directories: C:\Program Files\Microsoft SQL Server\MSSQL$WINCCFLEXIBLE\Data and C:\MSSQL\Data.
8. Run the Siemens MSDE Cleanup Tool (referenced in Siemens support entry ID 22054701) if the registry audit still shows residual install traces. The tool reports "No conflict found" when no remaining traces exist.
9. Reboot to clear any locked handles on the deleted directories.

Step 2 - Activate Microsoft Message Queuing (MSMQ)

MSDE 2000 and SQL Server 2005 Express both require MSMQ for internal service communication, asynchronous trigger execution, and the replication services used by WinCC Flexible's alarm logging runtime and recipe management. Without MSMQ enabled, the SQL Server service fails to start post-installation and the WinCC Flexible setup rolls back the entire transaction.

1. Open Control Panel → Add or Remove Programs (Windows XP) or Programs and Features (Windows 7).
2. Click "Add/Remove Windows Components" on the left pane.
3. Check "Message Queuing Server" and, if listed, "Message Queuing Triggers" sub-option.
4. Click OK and provide the Windows installation media when prompted.
5. Reboot after the MSMQ install completes so the kernel-level driver loads.

Verify the service is running from an elevated command prompt with sc query msmq. Expected output: STATE: 4 RUNNING. Also confirm mqsvc.dll is registered via regsvr32 /s mqsvc.dll if the service starts and stops immediately.

Step 3 - Address Microsoft Office 2003/2007 Conflict

The MSDE 2000 installer shares Windows Installer file hash tokens with Microsoft Office 2003 and 2007 components. When Office is installed, the MSI database Office12.msi or Office11.msi takes precedence over the embedded MSDE installer files and the install rolls back with "Internal Error 2711" or "Error 1603". The hash collision is well documented in Microsoft's Windows Installer error 2711 reference.

1. Uninstall Microsoft Office 2003 or 2007 in Add or Remove Programs. Use the Microsoft Fix-it removal tool if standard uninstall fails: Microsoft Program Install and Uninstall Troubleshooter.
2. Delete the Office installation source folder to prevent MSI hash collisions: C:\MSOCache\All Users and any user-specific MSOCache subfolders.
3. Remove leftover Office registry entries under HKLM\SOFTWARE\Microsoft\Office and HKCU\SOFTWARE\Microsoft\Office.
4. Reboot and re-run WinCC Flexible setup with administrator privileges.

If Office 2007 is a business requirement, retain it and install MSDE manually using the procedure in Step 4, bypassing the bundled installer entirely.

Step 4 - Manually Install MSDE Before WinCC Flexible

Bypassing the embedded MSDE installer removes the dependency on the Siemens Setup wrapper's transaction handling. Manual install permits verbose logging and gives full control over the instance name, service account, and authentication mode. Use this procedure when Step 1 through Step 3 do not resolve the install failure.

1. Insert the WinCC Flexible DVD or mount the ISO.
2. Open a command prompt as administrator (cmd.exe → right-click → Run as administrator).
3. Change directory to the MSDE payload: cd /d D:\MSDE\DISK1\MSDE (substitute the actual DVD drive letter; on WinCC Flexible 2008 SP5 the path may be D:\SQL\).
4. Run setup with the parameters below. The password must contain at least one uppercase, one lowercase, one digit, one symbol, and be 8 characters or longer to satisfy SQL Server 2000/2005 strong password policy.

5. Wait for completion (typically 60-90 seconds on Windows XP SP3).
6. Verify the install by querying the SQL Server version from the command line:

Expected output begins with: Microsoft SQL Server 2000 - 8.00.2039 (Intel X86) or, for WinCC Flexible 2008 SP5, Microsoft SQL Server 2005 - 9.00.5000.00 (Intel X86).

7. Inspect C:\msde_install.log for any warnings about authentication mode, collation, or service startup. Address each warning before proceeding to Step 5.

Step 5 - Install WinCC Flexible with Custom Setup

1. Re-insert or remount the WinCC Flexible DVD.
2. Run setup.exe as administrator.
3. Select "Custom Installation" in the setup dialog.
4. In the component tree, deselect the "MSDE / SQL Server" component — it is already installed and starting manually.
5. Choose the WinCC Flexible components required: ES (Engineering Station), Runtime, Communication drivers (PROFIBUS, PROFINET, MPI).
6. Accept the default install path C:\Program Files\Siemens\WinCCFlexible unless corporate standards dictate otherwise.
7. Enter the licensing data or activate the floating license server address.
8. Complete the wizard. The installer should skip the SQL step entirely and proceed directly to file copy.

Step 6 - Install WinCC and WinCC Flexible on the Same PC

When the host runs WinCC (SCADA) alongside WinCC Flexible, the install order is critical. The WinCC product ships its own SQL Server instance (default instance name WINCC) and uses different SQL authentication rules from the MSDE 2000 instance deployed by WinCC Flexible.

1. Install WinCC first. Allow it to install its bundled SQL Server 2005 Express instance.
2. Reboot and verify the WinCC instance with osql -S .\WINCC -E -Q "SELECT @@VERSION".
3. Install WinCC Flexible second. The setup detects the existing SQL Server and installs MSDE into a separate instance named WINCCFLEXIBLE on a separate port (default 1434 to avoid collision with the WINCC instance).
4. If WinCC Flexible is installed first, the WinCC setup will reject the SQL configuration and require a manual SQL reinstall of the WINCC instance, doubling the deployment time.

Error Code and Log Reference

Network Protocol and Service Configuration

After the MSDE 2000 install completes, the SQL Server service by default listens on Named Pipes only. WinCC Flexible Runtime, when deployed across a panel-to-PC network, requires TCP/IP enabled on port 1433 (or the named instance dynamic port). Use the SQL Server 2000 Network Utility (svrnetcn.exe) to enable additional protocols:

1. Run svrnetcn.exe from C:\Program Files\Microsoft SQL Server\80\Tools\Binn.
2. Select the WINCCFLEXIBLE instance.
3. Enable TCP/IP. Set the default port to 1433 to allow predictable firewall rules, or enable the SQL Server Browser service on UDP 1434 for dynamic port assignment.
4. Enable Named Pipes for local inter-process calls on the same host.
5. Stop and restart the MSSQL$WINCCFLEXIBLE service from services.msc.

For WinCC Flexible 2008 SP5 deployments using SQL Server 2005 Express, use the SQL Server Configuration Manager (SQLServerManager.msc) for the equivalent protocol configuration.

OS Compatibility Reference

Verification

1. Open WinCC Flexible via Start → Siemens Automation → WinCC Flexible → WinCC Flexible ES. Verify the project tree loads without SQL connection errors in the output window.
2. Create a new project, add an HMI tag with a real variable, save the project, close WinCC Flexible, then reopen. Verify the project loads from SQL without re-prompting for credentials.
3. Open SQL Server Enterprise Manager (MSDE 2000) from C:\Program Files\Microsoft SQL Server\80\Tools\Binn\SQL Server Enterprise Manager.msc or SQL Server Management Studio Express (SQL 2005 Express) and confirm the WINCCFLEXIBLE instance is registered with databases CC_Library, CC_Alarming, and CC_Recipe.
4. From a command prompt, run sc query MSSQL$WINCCFLEXIBLE. Expected output: STATE: 4 RUNNING.
5. Start the WinCC Flexible Runtime simulation with a sample project. Add an alarm, trigger it, stop Runtime, restart Runtime. Verify the alarm persists across the stop/restart cycle.
6. Validate the SQL authentication handshake: osql -S .\WINCCFLEXIBLE -U sa -P "WinCC!2024Sec" -Q "SELECT name FROM sysdatabases". Expected databases listed include master, model, msdb, tempdb, and the WinCC Flexible libraries.

Troubleshooting Matrix

Migration to TIA Portal WinCC

For environments where the host OS is Windows 10 or Windows 11 and the legacy WinCC Flexible install path cannot be adapted, the supported migration target is TIA Portal WinCC (Comfort/Professional edition). The migration workflow is documented in Siemens support entry ID 22054701 and in the WinCC Flexible → TIA Portal migration manuals available on the Siemens support portal.

Project conversion uses the WinCC Flexible ES → TIA Portal converter built into the TIA Portal project view; however, panel image compatibility must be verified per HMI model (KTP, TP, OP, MP series) against the TIA Portal device catalog before cutover. Recipe data, alarm logs, and project libraries must be exported from the MSDE 2000 instance and re-imported into the TIA Portal SQL Server instance using the WinCC Recipe/Alarm Export tool.

For SQL Server install issues on Windows 11 with TIA Portal WinCC, follow Microsoft's Install SQL Server from the Installation Wizard reference rather than the legacy MSDE path. The newer SQL Server 2019/2022 Express payload bundles with TIA Portal V17+ does not share the MSDE file hash collisions and is not affected by the Office 2003/2007 installer conflict.

Best Practices and Hardening

1. Always install MSDE and WinCC Flexible on a dedicated engineering workstation. Do not co-locate Office, Visual Studio, or third-party development tools that share MSI file hashes.
2. Snapshot or image the workstation immediately after a successful install so future recoveries do not repeat the SQL configuration.
3. Move the SQL Master, MSDB, and TempDB files to a dedicated non-OS volume to prevent drive-space exhaustion from taking down the engineering environment.
4. Schedule weekly DBCC CHECKDB jobs on the WINCCFLEXIBLE instance to detect page corruption early.
5. Maintain a documented SA password in a corporate password vault. The default blank SA password is rejected by strong-password policy enforcement in SP2+.
6. Disable the SQL Server Browser service on the engineering host if no other SQL instances are running. This reduces UDP 1434 attack surface.
7. Restrict inbound TCP 1433 and UDP 1434 on the engineering workstation firewall to the panel IP range only.

FAQ