Resolving Missing WinCC Component Object Manager Installation

Problem Overview

The WinCC Component Object Manager (also referenced as Component Object Manager, OM, or AS-OS Engineering component) is the optional install package that enables the bidirectional link between a STEP 7 / SIMATIC Manager project and a WinCC station. When the package is not present, the operator receives the dialog "Missing software package > WinCC (Component Object Manager)" when opening an integrated WinCC V7 project in the SIMATIC Manager, when launching the WinCC Explorer against an integrated project, or when the OS (Operator Station) compile is invoked from STEP 7.

The error typically appears under one of the following conditions:

• A custom install (user-defined) was performed and the Object Manager check box was deselected.
• WinCC was installed before STEP 7, leaving the AS-OS bridge unregistered.
• An uninstall/reinstall sequence removed the OM components but left the WinCC project data intact.
• The installed WinCC version is older than the STEP 7 service pack on the same PC and the OM is not registered against the newer SIMATIC Manager shell extension.

Siemens documents this behavior in entry 109815085: "Why does the message 'Missing software package > WinCC (Component Object Manager)' appear when opening a WinCC V7 project?" The official answer confirms two root causes: the OM was not enabled during WinCC install, or WinCC was installed first and STEP 7 was added later.

Root Cause Analysis

The Component Object Manager is a registered COM server plus an extension to the SIMATIC Manager shell that exposes WinCC project objects (OS, OS-Project, Tag, Alarm, Picture) as children of the S7 station tree. Without this DLL set registered, the SIMATIC Manager cannot traverse the OS sub-tree and emits the missing-package prompt. The component depends on three layers being present on the same workstation:

1. WinCC V7 Runtime and/or Configuration (the WinCC binaries themselves).
2. STEP 7 / SIMATIC Manager (the S7 project shell that hosts the OS objects).
3. The WinCC Object Manager add-in (the bridge layer between the two).

Installation order matters because the Object Manager is a per-product adapter. If WinCC installs first, it cannot know which STEP 7 path/HKEY to register against; the installer quietly skips the OM. If STEP 7 is installed afterward, the bridge never gets written, and the next time SIMATIC Manager opens a project with an embedded OS, it cannot resolve the component and raises the missing-package dialog.

Affected Products and Versions

The Component Object Manager exists in the following WinCC V7 lines and is required when integrating the OS into a STEP 7 project:

For TIA Portal, the equivalent functionality is no longer called Component Object Manager; the integration is handled by TIA Portal → WinCC Professional / Unified as part of the TIA project model. The OM is a legacy concept specific to the classic WinCC V7 / STEP 7 V5.x coexistence.

Symptoms and Diagnostic Messages

Typical operator-visible symptoms when the OM is missing or unregistered:

• Dialog on project open: "Missing software package > WinCC (Component Object Manager)".
• SIMATIC Manager shows the OS as a red node, or the OS sub-folder is empty / hidden in the S7 station tree.
• Right-click on the OS in SIMATIC Manager → the Open in WinCC Explorer option is greyed out.
• WinCC Explorer → Help → About lists installed components but the entry "Component Object Manager" is absent.
• Compile OS (NetPro or SIMATIC Manager → OS → Compile OS) returns a message that the OM is not installed.
• Event log: Event ID 19030 or Event ID 19035 in Siemens Automation → WinCC log source, depending on the version.

To confirm the OM presence, open WinCC Explorer → Help → About → Installed software. The list should include a row named "WinCC Component Object Manager" together with its build number (e.g., WinCC Component Object Manager V7.5 + SP1). If the row is missing, the install path below must be retriggered.

Solution Path A — Modify Existing Installation (Recommended First Attempt)

This is the fastest, non-destructive path. It uses the already-installed WinCC media/setup and adds the missing component to the live installation. Works for WinCC V7.0 through V7.5 on Windows 7 SP1, Windows Server 2008 R2, Windows 10 (1607+), and Windows Server 2016/2019/2022 with the correct Windows compatibility patch installed (e.g., SIMATIC WinCC V7.5 — Windows Server 2019 / Windows 10 (1909) Readme).

1. Insert the original WinCC installation DVD (or mount the ISO containing the matching WinCC build). If the original media is unavailable, download the same SP level from the Siemens Industry Online Support (SIOS) portal: support.industry.siemens.com.
2. Close SIMATIC Manager, WinCC Explorer, and the WinCC CCProjectEditor.
3. Open the Windows Control Panel → Programs and Features (Windows 10/11) or Add or Remove Programs (Windows 7).
4. Locate the entry SIMATIC WinCC Runtime (or SIMATIC WinCC Configuration if only the configuration portion was installed). Right-click and select Change.
5. The setup launcher opens. Choose Modify (German: Ändern) — do not choose Repair or Uninstall.
6. When prompted, accept the license dialog and the user-defined install dialog.
7. Navigate to WinCC Expert → WinCC Runtime (and/or WinCC Configuration, depending on which package is missing the OM).
8. Enable the check box Object Manager. On older media (V7.0), the entry may be labeled Component Object Manager or appear under the Options branch.
9. Click Next → Install. The setup copies the OM DLLs and registers the COM server. A typical install of the OM-only takes 1–3 minutes.
10. Reboot the workstation. The OM registration writes to HKLM\SOFTWARE\Siemens\Automation\WinCC\Components\ObjectManager and registers the shell extension under the SIMATIC Manager GUID tree.

After reboot, validate by opening WinCC Explorer → Help → About and confirm the OM row is now present. Then open the integrated S7 project in SIMATIC Manager and verify the OS sub-tree is no longer flagged.

Solution Path B — Manual Expert Installation from Setup

If the entry SIMATIC WinCC Runtime in Programs and Features is missing, the OM cannot be added through the modify path. The full WinCC setup must be re-run. Per the SIOS article 109815085, the procedure is:

1. Launch the WinCC setup from the DVD root: Setup.exe (32-bit) or Setup64.exe (64-bit, V7.3+).
2. Accept the license agreement.
3. Select User-defined Installation (German: Benutzerdefiniert) — not the Typical / Standard install path.
4. Drill down: WinCC Expert → WinCC Runtime (and/or WinCC Configuration) → tick Object Manager under the optional components tree.
5. For components that must be re-installed (green arrow → red icon), choose This component will be installed on the local hard drive.
6. For components that are already present and should remain, leave the default All components will be installed... or set them to installed as currently configured.
7. Proceed to Next, then Install. The OM registers against the existing STEP 7 install if STEP 7 V5.x is present on the same PC.
8. Reboot.

Solution Path C — Reinstall with Correct Order

For workstations where the OM cannot be added through the modify or expert setup (corrupt install, mismatched service packs, Windows 10 build incompatibility), a clean reinstall with the correct order is the most robust path:

1. Uninstall WinCC V7 via Programs and Features. Accept the offer to Keep project data — this preserves the existing WinCC projects in C:\Program Files (x86)\Siemens\Automation\WinCC\WinCCProjects\.
2. Reboot.
3. Verify that STEP 7 V5.x is at a service pack level compatible with the target WinCC V7 build. Reference the SIOS compatibility list for the specific combination.
4. Insert the STEP 7 DVD and install STEP 7 V5.x (or upgrade to the required SP). The order STEP 7 first is critical.
5. Insert the WinCC DVD. Run Setup.exe / Setup64.exe in user-defined / expert mode and explicitly enable Object Manager.
6. Complete the install and reboot.
7. Open SIMATIC Manager → open the S7 project that contains the OS. Right-click on the OS node and choose Open Object in WinCC Explorer. The OS should open without the missing-package dialog.

Verifying the Component Object Manager

After any of the three solution paths, verify the OM is correctly installed and registered. Use the following checklist:

1. Installed software list: WinCC Explorer → Help → About → Installed Software. Confirm a row titled WinCC Component Object Manager exists with a build matching the WinCC V7 version.
2. Registry hive: Open regedit and confirm the key HKEY_LOCAL_MACHINE\SOFTWARE\Siemens\Automation\WinCC\Components\ObjectManager exists. On 32-bit WinCC on 64-bit Windows, look under HKLM\SOFTWARE\WOW6432Node\Siemens\Automation\WinCC\Components\ObjectManager.
3. Filesystem check: The OM DLLs should be present under %ProgramFiles%\Siemens\Automation\WinCC\bin\ (V7.0) or %ProgramFiles(x86)%\Siemens\Automation\WinCC V7\bin\ (V7.3+). Look for S7OM.dll, OMConfig.dll, and the OMHelp language resource DLLs.
4. COM registration: Run regsvr32 /u %ProgramFiles%\Siemens\Automation\WinCC\bin\S7OM.dll followed by regsvr32 %ProgramFiles%\Siemens\Automation\WinCC\bin\S7OM.dll to verify the DLL unregisters and re-registers cleanly. A DllRegisterServer succeeded message confirms the COM entry points are valid.
5. SIMATIC Manager tree: Open the integrated project in SIMATIC Manager. Expand the S7 station → expand the OS node. The OS should display sub-nodes for Tag management, Alarm logging, Graphics designer, etc. Right-click on the OS → Open in WinCC Explorer should be active.
6. Compile OS smoke test: From SIMATIC Manager, right-click the OS → Compile OS. The compile should start without the missing-OM error. Monitor the WinCC Compiler output window for the line "OS Compile: S7-OM bridge active" (text varies by version).

Common Pitfalls and Edge Cases

Mismatched SP levels. The OM is a per-build component. A WinCC V7.0 SP1 OM will not register correctly against a STEP 7 V5.5 SP4 shell, and vice versa. Always confirm that the SP level of WinCC matches the SP level of the bridge DLLs. The SIOS compatibility list (entry 21927773, see SIOS) lists the supported STEP 7 service pack for each WinCC V7 build.

Windows 10 / Server 2019+ compatibility. WinCC V7.0 and V7.0 SP1 are not officially supported on Windows 10 1809+. The OM install may technically succeed, but the shell extension registration can be lost after a Windows feature update. Upgrade to a current WinCC V7.4 SP1 / V7.5 build if running on Windows 10 20H2 or newer, and apply the matching Windows compatibility patch from the WinCC V7 download package.

Parallel install with TIA Portal. TIA Portal installs its own OS bridge (for WinCC Professional / Unified) and does not conflict with the legacy V7 OM, but TIA Portal V13 SP1 and earlier can overwrite the COM GUIDs and unregister the V7 OM. The fix is to repair-install the WinCC V7 OM (Path A) after any TIA Portal upgrade.

User Account Control (UAC). The OM setup writes to HKLM and %ProgramFiles%. Run Setup.exe / Setup64.exe as administrator, even on a local admin account. Without elevation, the COM registration silently fails and the modify path reports success without actually registering the DLLs.

Antivirus interference. Some endpoint protection suites quarantine S7OM.dll as a heuristic hit because the DLL loads in-process into SIMATIC Manager. Add an exception for the WinCC installation folder before running the modify or expert setup. Verify the DLL is present and not quarantined after install.

Multi-user environments (WinCC / WinCC Runtime on a server with multiple SIMATIC stations). The OM registers per workstation, not per project. A terminal server with multiple WinCC project folders only needs one OM installation; the bridge routes by project GUID at runtime.

Step-by-Step Decision Matrix

Documentation and Standards References

The following official Siemens documents govern the Component Object Manager install, registration, and version behavior. Verify against the latest revision of each entry on SIOS before deploying to a production SIMATIC PC station:

• SIOS 109815085 — "Why does the message 'Missing software package > WinCC (Component Object Manager)' appear when opening a WinCC V7 project?"
• SIOS 21927773 — Compatibility list STEP 7 V5.x ↔ WinCC V7 (search the SIOS portal for the current build).
• WinCC V7 Installation Manual (per version) — chapter User-defined Installation → WinCC Expert → Object Manager.
• WinCC V7 Release Notes — Windows compatibility section (e.g., Windows 10 20H2, Windows Server 2019, Windows Server 2022 patches).