Managing Installer Version Pre-Checks for Legacy Add-On Packages in SIMATIC PCS 7

On SIMATIC PCS 7 OS Clients, when an essential legacy engineering add-on package (such as PTE400) terminates installation because it demands an earlier service pack (e.g., V9.0 SP1 instead of V9.0 SP3), the installer is blocked by a version string pre-check in the Windows registry or MSI launch conditions. To deploy the package without downgrading the operating environment, temporarily modify the PCS 7 version string under 'HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Siemens\AUTS\PCS7' to match the expected version during setup execution, or edit the installer MSI to remove the restrictive LaunchCondition table entry using an MSI editor, restoring original registry values immediately after installation.

Executive Summary

In industrial process control environments with complex legacy equipment (such as power generation or high-voltage substation integration using specialized packages like PTE400 / Power Transmission Equipment), facilities frequently upgrade OS Clients to modern maintenance releases—such as SIMATIC PCS 7 V9.0 SP3—to benefit from vital security patches and performance improvements. However, specialized add-on packages often lack updated release certifications, maintaining hardcoded version checks that demand an exact legacy environment (e.g., terminating if PCS 7 V9.0 SP1 is not detected).

Having to install PCS 7 V9.0 SP1 on every new OS Client and sequentially apply SP2 and SP3 update packages imposes massive engineering delays and configuration overhead. Furthermore, extensive plant testing frequently confirms that the add-on's runtime graphics and scripts operate flawlessly on SP3. This guide explains how Siemens setup wrappers inspect system versioning and outlines proven administrative techniques—including temporary registry adaptation, MSI transform editing, and manual client graphic deployment—to install essential legacy add-ons on updated PCS 7 clients.

Architecture and Fundamental Mechanics

The Siemens software installation architecture enforces release dependencies through nested validation stages:

Setup Bootstrapper Version Checks:
- Siemens setup executables (Setup.exe) and Microsoft Installer (.msi) packages query the Windows Registry to determine the active PCS 7 release level.
- The primary registry keys inspected on 64-bit operating systems include:
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Siemens\AUTS\PCS7\Version
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Siemens\STEP7\CurrentVersion
- If the installed string (e.g., V9.0 SP3) does not match the hardcoded target string or regular expression in the setup configuration file (e.g., Setup.ini), the bootstrapper aborts with 'Unsupported PCS 7 version'.
MSI LaunchCondition Tables:
- Inside the Windows Installer database (.msi), the LaunchCondition table defines Boolean expressions evaluated before file copying begins.
- An expression such as PCS7VERSION = "V9.0 SP1" prevents execution on higher service packs even when internal binary APIs remain 100% backward compatible.
Client Project Architecture vs Full Setup:
- In WinCC Client-Server architectures, OS Clients do not execute controller engineering logic or compilation engines.
- Most specialized add-on packages on OS Clients provide only process pictures (.pdl), C-script function files (.fct), and bitmap resources.
- In many cases, copying the required graphic assets directly into the client's local directory or loading them via WinCC Server Data completely bypasses the need to execute the legacy setup package on the client station.

Step-by-Step Implementation Procedure

Follow these steps to deploy legacy add-on packages with restrictive version checks:

Method A: Temporary Registry Adaptation (Quick Setup Deployment)
1. Back Up Registry Key:
- Press Win + R, type regedit, and press Enter as Administrator.
- Navigate to:
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Siemens\AUTS\PCS7.
- Right-click the PCS7 key and select 'Export' to create a backup file (PCS7_Version_Backup.reg).

Temporarily Adjust Version Strings:
- In the right-hand pane, locate the string values Version, Release, and ServicePack.
- Temporarily edit the values to match the add-on's required version (e.g., change Version from 09.00.03.00 to 09.00.01.00, and ServicePack from SP3 to SP1).
Execute the Add-On Setup:
- Launch the add-on installer (e.g., PTE400 Setup.exe) as Administrator.
- The installer verifies the registry strings, passes the pre-check, and installs the required runtime files and templates.
Immediately Restore Original Registry Values:
- Double-click the exported PCS7_Version_Backup.reg file to restore the true PCS 7 V9.0 SP3 versioning, or manually re-enter original strings in regedit.
- Crucially, do NOT leave spoofed version strings in the registry, as this would cause future official Siemens updates to fail.

Method B: MSI LaunchCondition Editing (Silent IT Deployment)
1. Open Installer MSI in Orca:
- Obtain Microsoft Orca (standard Windows SDK MSI editing utility).
- Right-click the add-on's .msi file inside the setup folder and select 'Edit with Orca'.

Drop Restrictive Launch Conditions:
- In the left table list, click 'LaunchCondition'.
- Locate the row checking the PCS 7 version string (e.g., PCS7_VER_CHECK).
- Right-click the row and select 'Drop Row'.
- Select 'File > Save' to commit changes.
Run Setup Without Version Restrictions:
- Launch the modified installer: the installation completes cleanly without checking the service pack level.

Verification

Launch WinCC Explorer on the OS Client: verify that the add-on's menu extensions and graphic typicals are present.
Open WinCC Graphics Designer: confirm that add-on faceplates and picture templates load without script compilation errors.
Verify in SIMATIC Manager ('Help > About > Installed Software'): confirm that the host system correctly reports SIMATIC PCS 7 V9.0 SP3.
Activate WinCC Runtime: confirm that add-on faceplates open, communicate with OS Servers, and execute operator commands smoothly.

Limitations and Operational Precautions

Bypassing installer version checks is an advanced engineering workaround; it voids manufacturer compatibility guarantees for that specific package and must be validated through rigorous offline testing. Never deploy uncertified add-on packages to production systems without verifying that script APIs and active controls do not conflict with newer Windows or WinCC security policies. Software packages and licensing should be verified through an authorized Siemens distributor or the Siemens Industry Mall.

Engineer FAQ

Why do legacy add-ons block installation on newer PCS 7 service packs?

Because their setup routines include rigid version pre-checks in Setup.ini or the MSI LaunchCondition table designed before newer service packs existed.

Will temporarily changing the registry harm PCS 7?

No, provided the original registry strings are restored immediately after the add-on installation finishes.

What tool allows editing MSI launch conditions?

Microsoft Orca (or standard MSI database editors).

Can I copy add-on files to OS Clients manually without running setup?

Yes. If the add-on on OS Clients consists only of WinCC graphics (.pdl) and scripts (.fct), copying them to the local GraCS and library folders is often sufficient.