Resolving WinCC V7 Configuration Tool Errors with Excel 2003/2007

The WinCC V7 Configuration Tool enables bulk editing of mass data in WinCC projects through a Microsoft Excel interface. When the tool fails to launch, returns a COM/automation error, or corrupts the WinCC database, the fault almost always traces back to a Microsoft Office update, a Windows security patch, or an unsupported Excel version. This reference documents the verified root causes, the exact remediation steps, and the verification checks for the most common Configuration Tool failures on WinCC V7.0 and V7.0 SP1.

Problem Overview

Operators of the WinCC V7 Configuration Tool report one or more of the following symptoms when launching the tool from the WinCC project tree or from the Start menu:

• Excel starts but immediately closes; no template is loaded.
• Excel returns an automation error, "Microsoft Office Excel cannot access the file", or "Cannot use object linking and embedding".
• Excel 2003 launches, displays a blank workbook, and the Configuration Tool macros do not appear.
• Excel 2007 opens, the WinCC add-in tab is missing, and the worksheet returns #NAME? or #REF! errors on every cell.
• The Configuration Tool writes partial data to the project before terminating, leaving the WinCC database in a partially consistent state.

The tool itself is a thin Excel-based front end: it calls into the WinCC Configuration Tool add-in (CCTAddin.xla for Excel 2003, CCTAddin.xlam for Excel 2007) which in turn calls the WinCC OLE/COM automation interface. Any break in this chain — COM registration, add-in load, ACE/ODBC drivers, .NET interop, or macro security — surfaces as a startup or runtime error.

Root Cause Analysis

Siemens field reports and the official Smart Tools for WinCC entry consolidate the failure modes into three root causes.

Cause 1 — Conflicting Microsoft Security Update

Microsoft Update KB 96071 (as referenced in the original Siemens field incident; the exact bulletin number should be confirmed by sorting Windows Update history because Microsoft frequently re-issues or supersedes OLE and ODBC security patches) modifies components used by the Configuration Tool COM bridge. Once installed, the add-in fails to register its type library against Excel, and Excel returns an automation exception. The same effect has been observed with later cumulative updates that touched msado15.dll, mscomct2.ocx, and the Office File Validation engine.

Cause 2 — Unsupported Excel Version

Siemens only certifies the Configuration Tool against specific Excel versions. Excel 2007 is not on the certified list for the original WinCC V7.0 base release; the V7.0 SP1 Configuration Tool build extends support but does not certify every Excel 2007 build. Running an unsupported Excel produces either a hard COM error on launch or, worse, silent data corruption when the macro writes back to the WinCC database.

Cause 3 — Macro Security and Add-in State

Excel's Trusted Publishers list is empty on a fresh installation, so the WinCC self-signed macro certificate is rejected. The Configuration Tool templates use signed VBA; if the certificate is not trusted, Excel silently disables the project and the WinCC add-in does not load. The user sees a normal Excel window with no WinCC toolbar or ribbon entries.

Affected Products and Versions

Always confirm the installed WinCC build from the WinCC Explorer: Help > About displays the exact version string. The Configuration Tool version is reported in Excel via WinCC > About Configuration Tool once the add-in loads successfully.

Solution Path A — Remove the Conflicting Microsoft Update

This is the fastest path when the Windows Update history clearly shows KB 96071 (or any later OLE/ODBC security update) installed on the engineering station.

1. Close Excel and the WinCC Explorer.
2. Open Control Panel > Programs and Features > View installed updates.
3. Sort by Installed On descending; locate the security update referenced in the incident (KB 96071 or its successor).
4. Select the update, click Uninstall, and confirm.
5. Reboot the engineering station. Do not skip this step — the OLE subsystem holds open handles until the next logon.
6. Disable automatic update delivery for the Office and OLE components so the patch does not return:

   :: Windows 10/11 / Server 2016+
   gpedit.msc > Computer Configuration > Administrative Templates
     > Windows Components > Windows Update
     > Configure Automatic Updates = Disabled
   :: Windows 7 / Server 2008 R2
   wuaucpl.cpl > Change settings > Never check for updates
      (recommended for engineering stations)

7. Reinstall the WinCC Configuration Tool from the WinCC V7.0 installation media to refresh the add-in registration:

   "D:\WinCC\Setup\Setup.exe" /install
     or
   Start > SIMATIC > WinCC > WinCC Setup > Modify installation
     > check "Smart Tools > Configuration Tool"

8. Launch the Configuration Tool and confirm the WinCC ribbon/toolbar appears.

Solution Path B — Apply WinCC V7.0 SP1 (or Later)

If the engineering station must remain fully patched, the supported path is to upgrade the WinCC V7.0 base install to at least SP1, which contains a corrected CCTAddin that re-binds the OLE type library.

1. Verify the current WinCC build: WinCC Explorer > Help > About.
2. Insert the WinCC V7.0 SP1 DVD or mount the ISO.
3. Run Setup.exe from the root of the SP1 media. The installer detects V7.0 and performs an in-place upgrade.
4. Accept the default installation scope; ensure Smart Tools > Configuration Tool remains selected.
5. After the upgrade completes, restart the engineering station twice — once for the WinCC services, once for the SQL Server Express instance used by the WinCC project database.
6. Re-apply any project-specific license keys via Automation License Manager.
7. Launch the Configuration Tool. The add-in should now coexist with KB 96071 and any successor security update.

Apply SP2/SP3 in the same manner if the engineering station is part of a long-term maintenance fleet. Each service pack carries the cumulative set of Configuration Tool fixes and Office compatibility patches. Always record the resulting WinCC build and the Office build in the station's asset record.

Solution Path C — Use a Certified Excel Version

When the previous two paths are not available, downgrade or upgrade Excel to a version that is explicitly listed on the WinCC readme.

1. Open !\WinCC\Documents\English\WinCC_V70_Readme.pdf on the installation media.
2. Locate the Configuration Tool section under Smart Tools and confirm the certified Excel build (Excel 2003 SP3 or Excel 2007 SP2/SP3 depending on the WinCC SP level).
3. Remove any non-certified Office version via Programs and Features. Use the Office Custom Installation Wizard to perform a clean uninstall if multiple Office versions are present.
4. Install the certified Excel build from the original media. Do not perform a side-by-side install — only one Office version is supported on a Configuration Tool workstation.
5. After install, launch Excel once in safe mode to force a profile reset:

   excel.exe /safe

6. Close Excel, then run the Configuration Tool from the Start menu: SIMATIC > WinCC > Tools > Configuration Tool.

Configuration Tool Architecture and Excel Interface

The Configuration Tool is one of the Smart Tools for WinCC — a set of utilities that use Microsoft Excel as the editor for mass data such as tag names, alarm classes, picture names, and user rights. The components are:

A failure in any layer presents as a Configuration Tool error. The bridge layer (CCTCom.dll) is the most sensitive to Office security updates because it is registered as a COM in-process server and is loaded by Excel on demand. The automation server (WinCC.exe) is sensitive to SQL Server Express service state — confirm WinCC_SQL<InstanceName> is started in services.msc before launching the tool.

Macro Security and Publisher Trust

Even with the correct Excel version, the add-in will not load until the WinCC publisher certificate is trusted.

1. Launch Excel.
2. Open File > Options > Trust Center > Trust Center Settings > Trusted Publishers.
3. Confirm that Siemens AG appears in the list. If not, click Import and browse to %ProgramFiles%\Siemens\Automation\WinCC\bin\WinCCPublisher.cer on the engineering station.
4. Set Macro Settings to Disable all macros except digitally signed macros (Excel 2010+) or the equivalent for the installed version.
5. Restart Excel and launch the Configuration Tool.

Prevention and Hardening

• Isolate the engineering station from automatic Office updates. Engineering stations should be treated like a DCS controller: patch only after validation against a representative WinCC project.
• Maintain a project backup before every Configuration Tool session. The tool is reversible for tag import/export, but a mid-session crash can leave the WinCC database in an inconsistent state that requires a project restore.
• Document the certified Excel build on the station's asset record. Use a post-install verification script that exports the Excel version, the WinCC build, and the KB list:

  reg query "HKLM\SOFTWARE\Microsoft\Office\ClickToRun\Configuration" /v VersionToReport
  reg query "HKLM\SOFTWARE\Siemens\WinCC\Setup" /v Version
  wmic qfe list brief | findstr /R "KB[0-9]*"

• Keep the WinCC installation media and the Configuration Tool redistributable on a network share; an uninstall/reinstall is the cleanest remediation for a damaged COM registration.
• Apply WinCC service packs in lockstep with Office service packs. SP1, SP2, and SP3 each carry a refreshed CCTAddin for the current Office generation.
• Avoid running the Configuration Tool over a Remote Desktop session with bandwidth below 10 Mbps; macro execution and COM marshalling can time out and corrupt the project write.

Verification Procedure

After any remediation, run the following checks before resuming production engineering:

1. Launch the WinCC Explorer and confirm the project opens without database errors.
2. Start the Configuration Tool from the Start menu. Excel must open with the WinCC add-in tab visible.
3. Run a small export/import round-trip on a single test tag. Verify the tag appears in the WinCC Tag Management and that the value is correct.
4. Close the Configuration Tool, then close Excel. Confirm the WinCC Explorer remains stable and the project does not flag "configuration changed" on close.
5. Open the Windows Event Viewer, Application log, and confirm no new CCT or Office errors were written during the round-trip.
6. Recompile the project (WinCC Explorer > Tools > Compile OS) and confirm no references are flagged as missing.

Troubleshooting Matrix

Related Siemens Resources

The Smart Tools for WinCC entry (SIOS ID 13681075) in the Siemens Industry Online Support portal lists the full Configuration Tool feature set, the certified Office versions per WinCC service pack, and the change history of the add-in. Always cross-check the latest readme on the SIOS portal before applying a new Office cumulative update to an engineering station.