Resolving WinCC Flexible ActiveX Errors: OCX Registration Guide

Overview

ActiveX (OCX) controls extend the runtime behavior of Siemens WinCC Flexible and the successor WinCC Comfort/Advanced (TIA Portal) HMI projects with custom COM-based objects such as calendars, file dialogs, charting OCXes, vendor-specific drivers, and third-party visualization widgets. When an ActiveX control is referenced in a screen, script, or alarm configuration but the underlying OCX file is not registered on the host that opens the project (engineering station) or the runtime target (Panel, RT PC, or WinCC Flexible Runtime), WinCC produces a hard failure during compile, transfer, or runtime startup. Typical symptoms include the runtime popup "The control is not installed", missing graphics, blank object frames, or the screen refusing to load entirely.

This reference covers the full OCX lifecycle for WinCC Flexible 2008 SP2/SP3/SP4/SP5 and the migration path into TIA Portal V13–V18 WinCC Comfort/Advanced, including registration on 32-bit and 64-bit engineering workstations, target deployment to SIMATIC Panels (e.g., KTP, TP, MP, Comfort), and the blocking semantics introduced when ActiveX calls are chained from VBScript. Each procedure uses the official Siemens support entry 37022154 as the authoritative registration procedure and cross-references Microsoft ActiveX policy guidance from Microsoft Office support where IE-based hosting applies.

Problem Identification

ActiveX-related failures in WinCC Flexible manifest in three distinct phases:

Engineering Phase (Configuration PC)

• Symbol not found in SmartRepository / Library: The OCX appears under Controls > ActiveX in the WinCC Flexible toolbox but cannot be inserted; tooltip shows "Class not registered".
• Compile error 130001 / 130002: Generated when an ActiveX wrapper references a missing typelib (TLB) or missing dispatch interface (IDispatch).
• Project opens but screens show red X / question mark: Indicates the ActiveX control was registered on the original programmer's PC but the OCX file or its registry entries are missing on the current workstation.

Transfer Phase

• ProSave transfer aborts at 87%: Caused by unsupported OCX in the runtime image; the panel's firmware rejects the ActiveX container.
• CompactFlash / USB transfer warning: "Component <OCXNAME> cannot be transferred" when the target firmware does not bundle the OCX runtime.

Runtime Phase (Panel or PC Runtime)

• Popup: "The control is not installed on this device." This is the canonical error produced when the OCX is present in the project but unregistered on the runtime host.
• Runtime freezes / script timeouts: A blocking COM call inside the ActiveX stalls the entire VBScript queue, blocking alarm logging and screen switching.
• Black screen after change: After a screen change to the ActiveX host screen, no further events fire until the device is rebooted.

Root Cause Analysis

ActiveX controls require two parallel artifacts to function on Windows-based hosts:

1. The OCX/DLL binary physically present in a directory on the file system (commonly C:\Windows\System32 on 32-bit Windows, C:\Windows\SysWOW64 on 64-bit Windows for 32-bit OCXes).
2. COM registry entries under HKEY_CLASSES_ROOT\CLSID\{GUID} and HKEY_CLASSES_ROOT\TypeLib\{GUID} that map the ProgID to the binary path and the IDispatch interface.

When a project is copied from one engineering PC to another, or compiled on a station that never had the third-party control installed, the binary is missing and/or the registry hive has no record of the CLSID. The most frequent root causes observed in field deployments are:

The Siemens support article 37022154 explicitly states that every OCX referenced by the project must be present on both the engineering station and on each runtime target, and that the registration must be performed with elevated rights using RegSvr32.

Prerequisites

Before registering an OCX in a WinCC Flexible environment, confirm the following:

• Administrator privileges: Both interactive admin (engineering PC) and full admin on the runtime target. Standard users cannot write under HKEY_CLASSES_ROOT or to %SystemRoot%\System32 on modern Windows builds.
• WinCC Flexible installation media or installed runtime: Required to confirm which OCXes are bundled by Siemens (e.g., Microsoft Date and Time Picker, Microsoft Common Dialog Control) versus third-party OCXes supplied by the original project author.
• Original OCX installation package: For proprietary OCXes (vendor or custom), obtain the install media or the OCX plus its .dep dependency manifest from the project originator.
• Matching bitness: WinCC Flexible 2008 SP2–SP5 and WinCC Comfort/Advanced are 32-bit applications even on 64-bit Windows. Therefore the OCX must be 32-bit and must be registered to the 32-bit COM hive (SysWOW64\regsvr32.exe on a 64-bit OS).
• PowerShell or CMD with administrator elevation: Used for executing regsvr32 and verifying registry entries.
• ActiveX hosting rights (PC Runtime only): On Windows 7 and later, the host process must have permission to instantiate COM objects. Refer to Microsoft ActiveX settings guidance for the policy framework that may block instantiation.

Step-by-Step: Register an ActiveX OCX on the Configuration PC

The procedure below follows Siemens support entry 37022154 verbatim, with field-proven additions for 64-bit hosts.

Step 1 – Locate the OCX file

1. Determine the OCX filename and GUID from the WinCC Flexible project: Project → Used OCX lists every referenced control with its CLSID.
2. Copy the OCX (e.g., MyVendorCtrl.ocx) into C:\Windows\SysWOW64\ on a 64-bit OS, or C:\Windows\System32\ on a 32-bit OS.

Step 2 – Register with RegSvr32

1. Open Start > Run, type cmd, press Ctrl+Shift+Enter to launch an elevated command prompt.
2. On a 64-bit Windows host, navigate to the 32-bit registration binary: cd /d %SystemRoot%\SysWOW64
3. Register the OCX: regsvr32 MyVendorCtrl.ocx
4. On success, Windows displays "DllRegisterServer in MyVendorCtrl.ocx succeeded." If the dialog reports "module failed to load", the OCX has unresolved dependencies (typically a runtime DLL such as MSVCR120.dll or MFC42.dll). Install the redistributable and retry.

Step 3 – Verify the CLSID is present

1. Open regedit as administrator.
2. Navigate to HKEY_CLASSES_ROOT\CLSID.
3. Search for the GUID listed in Used OCX. The default value must point to the OCX path, and an InprocServer32 subkey must exist with the same path.

Step 4 – Insert the ActiveX in the WinCC Flexible project

1. In WinCC Flexible ES, open the screen, select Controls > ActiveX from the toolbox.
2. The registered OCX now appears in the list under its ProgID. Drag it onto the screen.
3. Configure the interface in the Properties window; the IDispatch methods exposed by the OCX become available in VBScript via the object's name.

Step 5 – Compile and test locally

1. Compile the project with Project → Compiler → All.
2. Launch WinCC Flexible Runtime locally to verify the control renders and responds to input.

Step-by-Step: Deploy the OCX to a SIMATIC Panel Target

Most SIMATIC Panels (KTP, TP177, MP277, Comfort Panels) ship with a fixed runtime image. Only a subset of OCXes are bundled in the firmware; refer to the panel's Readme for the supported list. For OCXes not bundled by Siemens, two deployment paths exist:

Path A – OCX Already Supported by Panel Firmware

1. Insert the ActiveX into the project as described above.
2. During transfer, ProSave bundles the necessary runtime support automatically.
3. Transfer with Project → Transfer → Panel.

Path B – Custom OCX on PC-based Runtime (WinCC Flexible RT or WinCC RT Advanced)

1. Copy the OCX to the runtime PC's SysWOW64 directory.
2. Register with elevated regsvr32 exactly as in the configuration procedure.
3. If the runtime runs as a service, restart the WinCC Flexible Runtime service so the COM catalog is re-read.
4. On Windows 7 / Server 2008 R2 and later, ensure the Desktop Experience feature is installed; the COM subsystem requires it.

Path C – Comfort Panel OCX Plug-in (TIA Portal)

Starting with TIA Portal V14 and WinCC Comfort/Advanced V14 SP1, Siemens supports signed OCX plug-ins for Comfort Panels via the Add-In mechanism. The OCX must be signed with a Siemens-issued certificate and packaged with Simatic_OCX_Tool.exe. Deploy the resulting .zip via the panel's Service → Add-Ins menu.

Script Blocking Considerations with ActiveX

When a VBScript in WinCC Flexible calls a method on an ActiveX control, the call is synchronous: the script engine blocks until the COM method returns. If the OCX implements a long-running operation (network I/O, blocking dialog, hardware polling), the entire WinCC Flexible Runtime script host is blocked. Consequences include:

• Alarm logging delays: The alarm subsystem shares the script dispatcher; an OCX that hangs for >5 seconds delays alarm acknowledgment across all screens.
• Screen change freeze: ActivateScreen calls queued behind the blocked OCX do not fire.
• Watchdog reset: Most panels reboot after 60 seconds of script-thread starvation.

Mitigation patterns:

' Pattern 1: Defensive timeout using a Timer control
Dim startTick
startTick = Now
Do While ocxCtrl.Busy = True
  If DateDiff("s", startTick, Now) > 3 Then
    SmartTags("OCX_Timeout") = True
    Exit Do
  End If
  Loop

' Pattern 2: Asynchronous dispatch via separate scheduled task
SmartTags("OCX_Request") = True   ' consumed by a scheduled VB script running every 500 ms

Project Migration: Moving a WinCC Flexible Project Between PCs

Migrating a project that contains ActiveX references is the most common trigger for "The control is not installed" errors. Follow this disciplined procedure:

1. Inventory the original project: Project → Used OCX. Export the list to CSV.
2. Export the OCX binaries from the original PC's SysWOW64 or the vendor install directory.
3. Document dependencies: Use Dependency Walker to capture the OCX's required DLLs (MSVC runtime, MFC, ATL).
4. Install the OCX on the new configuration PC using the vendor's installer if available; otherwise use the manual regsvr32 procedure.
5. Re-link CLSIDs: Some ActiveX controls store absolute CLSID references in the HMI tag database. Open the project, re-insert each control once, and re-bind the VBScript references.
6. Compile with Project → Compiler → All (with full rebuild). A partial compile may reuse stale cached wrappers.

ActiveX Security Settings and Group Policy

On PC-based runtimes (WinCC Flexible Runtime, WinCC RT Advanced), the OCX host is the same WebBrowser control used by Internet Explorer. ActiveX security policy therefore applies. Configure the following to allow COM instantiation from the runtime process:

For runtime hosts that publish HMI screens via WinCC WebNavigator, Microsoft documents the ActiveX gating workflow at Enable or disable ActiveX settings in Office files. The same KB article applies to the WebNavigator client OCX plug-in.

Troubleshooting Matrix

Verification Procedure

1. Configuration-side verification: Compile the project with full rebuild; confirm zero warnings referencing ActiveX. Open Runtime Simulator (Start → Programs → Siemens → WinCC Flexible → Runtime Simulator) and exercise the OCX.
2. Registry verification: reg query HKCR\CLSID\{GUID} /s from an elevated CMD must return the OCX path and InprocServer32 subkey.
3. Target-side verification: On the panel, navigate to Service → Information → OCX (where supported) and confirm the CLSID appears. On a PC Runtime, launch dcomcnfg and inspect the COM catalog.
4. Functional verification: Drive the OCX from a VBScript bound to a button event; confirm the call returns within <1 s and the screen remains responsive.
5. Regression verification: Force a screen change to the OCX host screen, then immediately back, 50 times; confirm no orphan timers or stuck script threads.

Parameter Reference Table

Best Practices and Field Notes

• Document every OCX at project creation time: filename, GUID, version, vendor, bitness, and dependency list. Store in a project VENDOR.md next to the .hmi source.
• Avoid blocking calls: Treat every OCX method call as a candidate for timeout. Default to <3 s watchdogs.
• Prefer built-in controls: WinCC Flexible and TIA Portal Comfort/Advanced ship with native trend, alarm, recipe, and scheduler controls. Replace OCXes with these where possible to eliminate the COM dependency entirely.
• Use 32-bit OCXes only: WinCC Flexible is 32-bit; never attempt to register a 64-bit OCX.
• Test on the actual panel: Simulators hide firmware-level OCX constraints. Always validate on the target hardware before sign-off.
• Schedule OCX refresh: When a vendor releases a new OCX version, retest all screens; a minor GUID or interface change can break legacy projects silently.