Resolving the WinCC 7.3/7.4 "A Basic Application Could Not Be Started, Please Check Your Software License" Error

Engineers maintaining legacy SIMATIC WinCC V7.3 and WinCC V7.4 SP1 projects frequently encounter the error dialog "A basic application could not be started, please check your software license" when attempting to open an existing project or create a new one in the WinCC Explorer. The error appears deceptively license-related, but the root cause is almost always a corrupted internal runtime state, an SQL Server version mismatch after a downgrade, or a missing patch level on the WinCC installation itself. This reference documents the diagnostic path and the field-proven remediation steps that Siemens technical support and the WinCC community have validated for V7.3 and V7.4 deployments.

1. Problem Overview

The failure pattern is consistent across reported cases:

1. The user uninstalls one WinCC version (typically V7.4) and installs an older one (V7.3 Update 1 or V7.3 SP1), or upgrades an existing V7.3 environment to V7.4 SP1.
2. WinCC Explorer launches and the project is created or opened.
3. The WinCC Explorer progress halts immediately after the Tag Management section begins to load.
4. The dialog "A basic application could not be started, please check your software license" appears.
5. A second follow-up dialog "Project could not be created" or "Project could not be opened" is raised.

The license indicator inside WinCC Explorer is green and shows a valid license. Windows itself is fully activated. SQL Server services (WINCC) are reported as Running. The error is therefore not a missing license key — it is a failure of one of the underlying COM/RTD/CCRuntime components that WinCC launches through its License Manager during project initialization.

2. Symptoms and Error Behavior

Capture the following symptoms during the failure so you can compare them with the diagnostic matrix in Section 4:

2.1 PMDiagnose Log Entries

Collect the PMDiagnose log from the affected machine. Two entries are diagnostic:

2016-12-09 15:28:50.915 PM(2768-5484) CCImpersonate::CCImpersonate failed
  for ImpersonateLoggedOnUser with error 6: The handle is invalid.

2016-12-09 15:28:51.352 PM(1000-6064) Parameter {1} ignored

The first line is the critical one. error 6 is the Win32 ERROR_INVALID_HANDLE returned by the ImpersonateLoggedOnUser Win32 API call. The CCImpersonate wrapper class is part of the WinCC Common Components (CC) layer and is invoked whenever a CC process needs to act under the credentials of the currently logged-on user. An invalid handle at this point typically means:

• The WinCC user profile lacks a valid logon token (broken user profile).
• The SQL Server instance is running under a different account than the user opening the project.
• UAC virtualization or service-hardening is denying the impersonation request.

The second line (Parameter {1} ignored) is informational and indicates that an option string passed to a CC routine was malformed — usually a remnant of an interrupted previous installation.

3. Affected Versions and Operating Systems

Operating-system compatibility is a separate constraint. WinCC V7.3 was not released for Windows 10. Siemens explicitly states that V7.3 is a Windows 7 product. Windows 10 deployments of V7.3 are tolerated but unsupported and may show exactly this dialog when CC runtime components initialize. Confirm the OS matrix with the official WinCC 7.3 / Windows compatibility thread (117587) and the Siemens Compatibility Tool before any remediation.

4. Root Cause Analysis

Four independent root causes have been verified in the field. The diagnostic matrix below maps symptom to cause so you do not waste cycles on the wrong remediation.

Root cause #1 is by far the most common. If you are running base V7.4 SP1, upgrade to Update 5 or later. If you are on V7.3, install Update 19 or later. Both patch packages address CCImpersonate/CCRuntime initialization regressions that produce this exact dialog.

5. Diagnostic Tools: SIMATIC Assessment Suite - Data Collector (SAS-DC)

Before any uninstall/reinstall cycle, capture a complete system snapshot with the SIMATIC Assessment Suite - Data Collector (SAS-DC, formerly SIMATIC Diagnostics Tool / SDT). It collects registry keys, installed software, Windows event logs, CC runtime state, SQL configuration, and WinCC project metadata in a single zip.

1. Download the SAS-DC from the official Siemens article: SIMATIC Assessment Suite - Data Collector (65976201).
2. Extract the zip and run StartDiagnostics.cmd as Administrator.
3. Select the WinCC scope and a target folder.
4. Wait for the collector to finish — typically 3 to 8 minutes.
5. Attach the resulting .zip to a Siemens Service Request (SR) via the Siemens Industry Online Support portal.

6. Solution Path A — Apply the Latest Cumulative Update

This is the first remediation to attempt. Both Update 5 for V7.4 SP1 and Update 19 for V7.3 contain fixes for the CCImpersonate/CCRuntime component that triggers the misleading "license" dialog.

6.1 Procedure for WinCC V7.4 SP1 → Update 5

1. Close WinCC Explorer and stop the WinCC Runtime (CCAgent, CCRuntime, CCESI, CCEClient).
2. Download Update 5 for WinCC V7.4 SP1 (109756812).
3. Extract the archive and run Setup.exe as Administrator.
4. Follow the installer prompts. The update is cumulative; you do not need intermediate updates.
5. Reboot the machine.
6. Open WinCC Explorer and verify project creation succeeds.

6.2 Procedure for WinCC V7.3 → Update 19

1. Close WinCC Explorer and stop all WinCC services.
2. Download Update 19 for WinCC V7.3 (109768972).
3. Run the update installer as Administrator.
4. Reboot and verify.

Field reports show that Update 6 or higher for V7.3 already eliminates the dialog in many cases. However, always target the latest available update (Update 19 at the time of writing) to inherit all subsequent fixes.

7. Solution Path B — SQL Server Cleanup After Downgrade

This path is mandatory whenever you downgrade from V7.4 to V7.3. WinCC V7.4 ships with SQL Server 2014; WinCC V7.3 requires SQL Server 2008. If you uninstall V7.4 without removing the SQL 2014 instance, the V7.3 installer will detect a "valid" SQL service but fail to bind WinCC to it, producing the license dialog at startup.

1. Open Control Panel → Programs and Features.
2. Uninstall Microsoft SQL Server 2014 (WINCC) completely. This includes the Database Engine, Replication, and any shared Management Tools.
3. Uninstall any leftover SQL Server 2014 Native Client entries.
4. Delete the residual data directories: %ProgramFiles%\Microsoft SQL Server\MSSQL12.WINCC and %ProgramFiles%\Microsoft SQL Server\MSSQL12.MSSQLSERVER if they remain.
5. Reboot.
6. Install WinCC V7.3 with its bundled SQL Server 2008 instance.
7. Verify SQL Server Configuration Manager shows SQL Server (WINCC) running under the local system or a domain service account.
8. Open WinCC Explorer and create a new project.

8. Solution Path C — Reset_WinCC.vbs

Siemens ships a Visual Basic reset script that reinitializes the WinCC Common Components and the SQL database configuration. It is the most direct fix for root cause #3 (corrupted CC runtime configuration).

1. Locate Reset_WinCC.vbs in the WinCC installation medium or in %ProgramFiles%\Siemens\Automation\WinCC\bin.
2. Open an elevated command prompt (Run as Administrator).
3. Execute: cscript.exe "C:\Program Files\Siemens\Automation\WinCC\bin\Reset_WinCC.vbs"
4. Allow the script to drop and recreate the CCArchiveManager and CCRuntimeManager registry branches.
5. Restart the computer.
6. Launch WinCC Explorer and retry project creation.

If Reset_WinCC.vbs does not exist on your machine, you can recreate it manually with the canonical content published in the Siemens KB articles for the affected version. The script is a thin wrapper around reg delete commands against the HKLM\SOFTWARE\Siemens\WinCC\Common Components tree.

9. Solution Path D — Windows 10 Compatibility Considerations

WinCC V7.3 was not released for Windows 10. Siemens does not guarantee correct behavior. If the host operating system is Windows 10 and you must keep V7.3:

1. Verify the Windows 10 build against the official compatibility matrix using the Siemens compatibility tool.
2. Disable Windows Defender real-time scanning for the WinCC and SQL Server folders. Real-time scanning can cause the ERROR_INVALID_HANDLE condition during rapid file-open operations.
3. Confirm the user account running WinCC Explorer is a local administrator and that UAC is not silently elevating/filtering the COM impersonation.
4. If the issue persists, migrate the project to WinCC V7.4 SP1 Update 5+ on a Windows 10 build that is officially supported.

10. Solution Path E — Server-Client Configuration Recovery

For distributed (multi-user) projects, the dialog can appear on a client only, even when the server is healthy.

1. Confirm the server is reachable over the network and that the SQL Server (WINCC) service on the server is running.
2. Reboot the server. The client-side CCImpersonate cache is invalidated during the server boot sequence.
3. If the error persists, on the client delete the cached credentials under %APPDATA%\Siemens\WinCC\UserArchive and %LOCALAPPDATA%\Siemens\WinCC.
4. Re-launch the client and re-enter the project credentials.

11. Step-by-Step Recovery Procedure

Use this consolidated procedure when you do not yet know which root cause applies. The order is the most efficient path observed across multiple production environments.

1. Capture diagnostics. Run SAS-DC and save the zip. Export the PMDiagnose log to a safe location.
2. Verify the SQL pairing. Programs and Features must show SQL Server 2008 for V7.3 or SQL Server 2014 for V7.4. Mismatches must be resolved before any further step.
3. Apply the latest cumulative update. V7.3 → Update 19, V7.4 SP1 → Update 5 or later.
4. Run Reset_WinCC.vbs as Administrator and reboot.
5. Test project creation with a brand-new project (not an existing one) to isolate the failure from project-file corruption.
6. If the failure is on a client only, reboot the server and clear the client-side cache.
7. If the issue persists, uninstall WinCC completely (including the SQL instance), manually clean the registry branches, and perform a fresh install at the latest update level.
8. If the issue still persists, open a Siemens Service Request with the SAS-DC bundle attached.

12. Verification and Functional Testing

After applying any remediation, validate the fix with this checklist before returning the system to production:

13. Prevention and Best Practices

• Always target the latest cumulative update. Base SP1 media for V7.3 and V7.4 contain known CC runtime defects that are fixed in Update 5/Update 19.
• Do not downgrade WinCC versions in place. If a downgrade is unavoidable, fully remove the higher version (including the SQL instance) before installing the lower version.
• Maintain a vendor-supported OS. Use only Windows 7/Server 2012 for V7.3 and Windows 10/Server 2016 for V7.4 SP1 Update 5+.
• Disable antivirus real-time scanning for %ProgramFiles%\Siemens\Automation and the SQL data directories.
• Run WinCC Explorer always as Administrator, even when the logged-on user is a local admin. UAC virtualization can interfere with CCImpersonate.
• Schedule an SAS-DC snapshot before and after any patch campaign, and archive the zip on a network share.

14. Frequently Asked Questions