Resolving Microsoft SQL Server 2017 Installation Failures on Windows Server 2019 During PCS 7 V9.1 Setup

When installing SIMATIC PCS 7 V9.1 on Windows Server 2019 and the setup terminates prematurely with the error 'SQL Server 2017 (WinCC) setup can not complete the installation', the failure is typically caused by Windows Regional Format mismatches, Active Directory Domain Controller role conflicts, or Group Policy security restrictions. The WinCC instance of SQL Server 2017 strictly requires the operating system's Regional Format and System Locale to be set to English (United States) during installation; non-English regional formatting causes the database engine bootstrap initialization script to abort. Furthermore, PCS 7 and SQL Server 2017 cannot be installed on a Windows Server operating as an Active Directory Domain Controller. To resolve the failure, set the system locale to English (US), ensure the server is a member server or workgroup, and install from the DVD Support\SQL2017\ using elevated administrative rights.

The Role of Microsoft SQL Server 2017 in SIMATIC PCS 7 V9.1 and WinCC

In SIMATIC PCS 7 V9.1 (which integrates WinCC V7.5 SP2), the entire supervisory data architecture is built on Microsoft SQL Server 2017 Standard Edition (64-bit). The SQL Server instance—named WINCC—serves as the centralized repository for:

Configuration Data (CS): Graphic screens (*.pdl), tag management, text libraries, user rights, and alarm definitions.
Runtime Data (RT): Short-term and long-term alarm logging journals (*.mdf), cyclic process value archives, and user archive tables.

Because WinCC relies on deeply customized SQL instance parameters (specific SQL collations, service account rights, and memory caps), Siemens deploys SQL Server 2017 via an automated setup wrapper. If any Windows system prerequisite fails, the wrapper aborts, halting the entire PCS 7 installation.

Root Cause 1: Windows Regional Settings, System Locales, and Collation Conflicts

The most prevalent root cause of SQL Server 2017 installation aborts is Windows Regional Format and Locale misalignment:

SQL Server Collation Requirement: The WinCC database instance mandates the binary collation SQL_Latin1_General_CP1_CI_AS.
Bootstrap Failure: If the host Windows Server 2019 is configured with non-standard regional formats (e.g., Persian, Arabic, Turkish, or mixed date/currency formatting), the SQL Server setup bootstrap script fails when attempting to create system databases (master, model, tempdb).
The setup logs an unhandled exception: Error 0x84bb0001: The database engine initialization script failed.
Remedy: Temporarily switching the Windows Regional Format, Administrative System Locale, and Display Language to English (United States) before running setup resolves the issue in over 80% of reported field cases.

Root Cause 2: Active Directory Domain Controller Constraints

In corporate and industrial IT networks, IT administrators sometimes attempt to install PCS 7 OS Servers on machines configured as Active Directory Domain Controllers (DC):

Strict Siemens Prohibition: Siemens and Microsoft strictly prohibit installing WinCC or SQL Server 2017 on an active Domain Controller.
Security Account Failure: On a Domain Controller, local Windows security accounts (SAM) do not exist; all accounts are domain-level. The SQL Server 2017 installer attempts to create dedicated local virtual accounts (NT SERVICE\MSSQL$WINCC, NT SERVICE\SQLAgent$WINCC). On a Domain Controller, this operation is rejected by Windows security, terminating setup with fatal permission errors.

Root Cause 3: Group Policy Restrictions (Log on as a Service and FIPS)

Corporate Group Policy Objects (GPOs) pushed to Windows Server 2019 frequently cause silent SQL installation aborts:

'Log on as a service' Rights: The local security policy SeServiceLogonRight must allow SQL Server virtual accounts to start services. If domain GPOs strip this right from local accounts, SQL services cannot start.
FIPS Compliance Enforcement: If the Windows policy 'System cryptography: Use FIPS compliant algorithms for encryption, hashing, and signing' is enabled, the legacy hashing algorithms utilized by SQL Server setup scripts are blocked, causing fatal setup crashes.

Comparative Fault Matrix: SQL Server 2017 Setup Failures

The following table details diagnostic symptoms, error codes, and remedies for SQL Server 2017 installation failures in PCS 7 V9.1:

Error Code / Log EntryUnderlying Root CauseVerification Log LocationCorrective ActionError 0x84bb0001Non-English System Locale / Regional FormatSetup Bootstrap\Log\Summary.txtSet Windows Locale & Region to English (US)Exit Code 0x84b40002Installation on Active Directory Domain ControllerWindows Server ManagerDemote DC or install on a clean Member ServerService startup timeoutMissing 'Log on as a service' user rightWindows Event Viewer -> SystemAdd NT SERVICE\ALL SERVICES to Local PoliciesFIPS Cryptography ErrorFIPS algorithm enforcement activeLocal Security Policy (secpol.msc)Disable 'Use FIPS compliant algorithms'Pending Reboot LockPendingFileRenameOperations activeWindows Registry (regedit)Clear registry value under Session Manager

Step-by-Step Recovery Procedure to Install SQL Server 2017 for WinCC

Follow this recovery procedure to achieve a clean SQL Server 2017 installation on Windows Server 2019:

Analyze Setup Bootstrap Logs:
- Navigate to C:\Program Files\Microsoft SQL Server\140\Setup Bootstrap\Log\.
- Open Summary.txt and locate the 'Detailed results' section to identify the exact failing component (e.g., SqlEngineConfigAction).
Standardize Regional and Language Settings:
- Open Windows Control Panel -> Clock and Region > Region.
- Under the Formats tab, set Format to English (United States).
- Click the Administrative tab -> Change system locale....
- Set Current system locale to English (United States).
- Ensure the checkbox 'Beta: Use Unicode UTF-8 for worldwide language support' is UNCHECKED.
- Restart Windows.
Verify Local User Rights and Security Policies:
- Open Local Security Policy (secpol.msc).
- Expand Local Policies > User Rights Assignment.
- Open Log on as a service. Ensure Administrators and ALL SERVICES are included.
- Under Security Options, ensure System cryptography: Use FIPS compliant algorithms... is Disabled.
Execute Dedicated SQL Server Setup:
- Mount the PCS 7 V9.1 installation DVD.
- Navigate to the folder: Support\SQL2017\.
- Right-click Setup.exe and select Run as administrator.
- Allow SQL Server 2017 Standard (WinCC instance) to install independently.
Resume PCS 7 V9.1 Installation:
- Once SQL Server completes successfully, launch the main PCS 7 Setup.exe.
- The installer will detect the healthy SQL instance and proceed with WinCC installation without errors.

Verification

Verify SQL Server 2017 health through these diagnostic steps:

Open Windows Services (services.msc).
Confirm that SQL Server (WINCC) and SQL Server Integration Services 14.0 are present and Running.
Confirm that the service Startup Type is set to Automatic.
Open SQL Server Configuration Manager. Verify that TCP/IP and Shared Memory protocols are Enabled for the WINCC instance.
Launch WinCC Explorer. Create a new test project. Confirm that the WinCC database mounts in SQL Server without connection errors.

Limitations and Operational Precautions

Windows Server Editions: Only Windows Server 2019 Standard and Datacenter (64-bit) are certified. Windows Server Essentials or Storage Server are not supported.
Manual SQL Uninstallation: If cleaning up a failed installation, uninstall all SQL components through Windows Programs and Features, delete the directory C:\Program Files\Microsoft SQL Server\MSSQL14.WINCC, and reboot before retrying.
Antivirus Scanning: Disable real-time antivirus scanning during SQL setup to prevent file-locking conflicts during binary extraction.

Engineer FAQ

Can I use SQL Server 2019 instead of SQL Server 2017 with PCS 7 V9.1?

No. PCS 7 V9.1 is strictly certified and hardcoded for Microsoft SQL Server 2017. Installing an uncertified SQL version will cause WinCC runtime archiving services to fail.

Why must the Windows locale be English (US) during installation?

The Siemens SQL Server setup wrapper executes configuration scripts that expect standard American date formats (MM/DD/YYYY) and English system error messages during instance creation. Once installed, the display language can be adjusted.

What is the difference between SQL Server Express and SQL Server Standard in PCS 7?

SQL Server Express is used only for lightweight tools like SIMATIC PDM. WinCC OS Servers require the full Microsoft SQL Server Standard Edition (included on the PCS 7 installation media) to support multi-gigabyte process value and alarm archives.

Where can I find the official SQL installation log files?

SQL Server writes detailed logs to C:\Program Files\Microsoft SQL Server\140\Setup Bootstrap\Log\.

Can WinCC run if the SQL Server Agent service is stopped?

Yes. WinCC primarily requires the database engine SQL Server (WINCC). The SQL Server Agent is used for scheduled maintenance tasks and database backups.