Resolving WinCC RT Advanced Logging License Not Found Warning

Problem Definition

On startup, WinCC Runtime Advanced for SIMATIC Panels and PC-based HMI systems displays a dialog titled "WinCC logging for Runtime Advanced license not found". The dialog requests the operator to install a valid license for the logging feature, even when the engineering project contains no explicitly configured data logs, alarm logs, or audit trails. The warning recurs on every Runtime boot, blocks license-compliant startup, and indicates a mismatch between the licensing expectations embedded in the compiled runtime image and the actual configuration of the project.

This issue is documented across TIA Portal versions V15.1, V16, V17, V18, V19, and V20 and is not specific to a single firmware build of a Comfort Panel, Unified Comfort Panel, or PC-based Runtime. The reported environment in the field case is TIA Portal V16 on Windows 10, but the same diagnostic and remediation path applies to subsequent versions.

Licensing Model and Why the Warning Appears

WinCC Runtime Advanced uses a single runtime license (RC) per device. Optional add-ons, including the Logging option (historically a USB stick or ALM-based license with the designation WinCC RT Advanced Logging), unlock the persistent storage of tags and alarms. When the compiler detects the use of any feature that touches the logging subsystem, it embeds a license check in the generated runtime image. The runtime executes this check on every start, and if no valid license key is found, the dialog appears.

The compiler decides whether a logging license is required based on what is actually compiled into the image, not what is currently active in the HMI screen. Therefore, even invisible configuration objects — such as a Data Log whose trigger condition is never met, an Alarm Log configured for "Logged" class, or an Audit Trail from a Good-Manufacturing-Practice (GMP) project — are sufficient to force the check.

Feature Set That Triggers the Logging License

For the canonical data logging behavior across Basic Panels, Comfort Panels, RT Advanced, and RT Professional, refer to the official TIA Portal help: Data logging (RT Professional) - WinCC. The same architectural rules apply to RT Advanced for cyclic, acyclic, and selective logging.

Root Cause Analysis

Five independent root causes have been observed in TIA Portal V16 ± higher. In practice, two or more coexist.

1. Stale or implicit data logs. The project contains a Data Log object in Historical data → Data logs that the engineer did not notice, often created by a copy/paste of a screen that referenced a log. TIA does not auto-delete empty data logs when their triggering tag is removed.
2. Alarm log inheritance. The active alarm class (typically "Errors" or "Warnings") has the Logged property set, and the Alarm Log object under Alarms → Alarm Logging is configured even without explicit tag retention.
3. Audit Trail / GMP enabled. The Runtime settings include an Audit configuration. This is the most frequent cause in regulated projects and silently re-enables itself after a project copy.
4. Corrupt or mismatched IM folder. The Installation Manager folder inside the project path contains references compiled against a different TIA version, a different Panel image, or a different HMI device. This is described in the official Siemens FAQ 109778709.
5. Outdated Automation License Manager (ALM). ALM older than V6.0 SPx may not release or validate keys correctly, causing a perpetual "not found" state for keys that are actually present. The current release is documented at SIOS entry 114358.

Diagnostic Procedure

Run the following checks in order. Each one is non-destructive and can be performed on a live engineering workstation.

Step 1 — Identify the exact TIA Portal version

Open TIA Portal → Help → Installed Software. Record the exact build, for example TIA Portal V16 Update 7 with HMI V16.0.0.0. Mismatch between TIA Portal and HMI option packs is a known source of phantom log objects.

Step 2 — Inspect the project tree

1. Expand Historical data. If any Data Log is listed, open it. If the Tags column is empty but the log name is non-default (e.g., DataLog_1), it is a stub from a prior version.
2. Expand Alarms → Alarm Logging. If an Archive Configuration exists, right-click and select Properties. The presence of an Alarm Log object — even with no Logged alarms — embeds the license check.
3. Open Runtime settings → User administration. Verify that Log user changes is unchecked.
4. Open Runtime settings → Audit. If the Audit node is present, GMP is enabled and a logging license is mandatory.

Step 3 — Check the compile output

Compile the HMI device to the target. Scroll to the end of the Compile output window. If a logging license is required, TIA prints a warning that explicitly states "Logging license required" and lists the affected features. This is the single most reliable indicator.

Step 4 — Validate the IM folder

Close TIA Portal. Navigate to the project folder (the directory that contains the .ap16 file). List the contents. If an IM subfolder exists, it must be examined against the project's current HMI device target. Per the official FAQ, the IM folder stores installation manifests; a stale one will desynchronize the compile results from the runtime expectations.

Solution A — Remove Data Logs

1. In the project tree, right-click Historical data → Data logs.
2. Select Delete all data logs. Confirm the dialog.
3. Open the HMI tags editor. Search for tags whose Acquisition mode is Cyclical logging or On change logging. These tags silently reference a Data Log even when no explicit log object is visible. Reset the acquisition mode to On demand or Cyclical (without logging) for every tag.
4. Recompile the HMI device. Verify the Compile output no longer references the logging license.

Reset of existing tag logging

If the logs were already created in the running runtime (for example on a Comfort Panel that had a logging license at one point), the storage files remain. For Panels that run WinCC RT, follow the procedure from SIOS 17853608: open the Alarm Logging editor in the WinCC Explorer, click Archive Configuration, right-click Alarm Log, and clear the archive. The same pattern applies to Tag Logging archives.

Solution B — Remove Alarm Logs

1. Open Alarms → Alarm Logging.
2. Right-click the Alarm Log object and select Delete. If the option is greyed out, the log is referenced by an alarm class; proceed to step 3.
3. Open each alarm class ("Errors", "Warnings", "System") and clear the Logged checkbox for every event. In TIA Portal V16 the property is on the Properties → General tab of the alarm class.
4. Open the Alarm View screen object on every HMI screen. Switch the Filter property from Log to Active alarms or Logged alarms (unacknowledged). The "Log" filter mode forces the runtime to query the historical archive, which in turn forces the license check.
5. Recompile.

Solution C — Audit Trail / GMP Configuration

Audit and GMP are the most common reason a license warning survives a complete log purge. The audit subsystem writes to a tamper-proof archive and is licensed separately.

1. Open Runtime settings → Audit.
2. If the audit node is not present in non-regulated projects, skip this solution.
3. If present, decide between the two valid paths:
   • Disable Audit: Clear the Enable audit checkbox. This removes the license requirement at the cost of losing the audit trail. Acceptable for non-regulated machines.
   • Keep Audit and license it: Acquire the WinCC RT Advanced Audit license via ALM. The runtime will then start cleanly without the warning.
4. Recompile after the change. The compile output will no longer list the logging license as required.

Solution D — IM Folder Reset

The IM (Installation Manager) folder caches the install state of every option pack referenced by the project. When a project is upgraded across TIA versions or copied between workstations, this folder can retain references to a logging feature that has since been removed from the editor. Per the Siemens FAQ 109778709, the IM folder must be deleted under specific conditions.

1. Close TIA Portal completely on all open instances.
2. Using Windows Explorer, navigate to the project directory (the folder containing *.ap16 or *.ap17).
3. Delete the IM subfolder. Do not delete any other folder.
4. Open the project. TIA Portal will rebuild the IM contents on the next compile.
5. Recompile the HMI device. Confirm the warning is gone.

Solution E — ALM Update and Full Recompile

1. Open SIOS entry 114358 and download the current Automation License Manager release. As of the V16 era the supported ALM is V6.0 SPx or higher; on V17+ use the ALM that ships with the respective TIA DVD/Online Software Delivery.
2. Install ALM. Restart Windows.
3. In TIA Portal, select the HMI device. Right-click → Compile → Software (rebuild all). Do not use the incremental compile; the full rebuild regenerates the runtime image and clears all cached license flags.
4. Download the project to the panel or PC runtime.

Verification Procedure

After applying the solutions above, perform the following verification sequence to confirm the warning is eliminated and no functional behavior is lost.

1. Compile output. Compile the HMI device. The output window must not list "Logging license required" or "Audit license required".
2. Download and start. Download to the target. Cycle power to the panel. The "license not found" dialog must not appear.
3. Alarm View test. Trigger a discrete alarm. Verify that the alarm appears in the Alarm View and that the acknowledgment cycle works.
4. Tag persistence test (if logging is licensed). If a logging license is actually required by the application, set a value, wait one logging cycle, and verify the CSV or RDB file is written.
5. Audit Trail test (if GMP). Log in as a GMP user, perform a set-value action, and confirm the audit record is generated and signed.

Troubleshooting Matrix

Field-Proven Caveats

• Alarm View filter "Log". The most frequent overlooked trigger in projects where the engineer has no logs at all. A single Alarm View with the filter set to Log forces the runtime to instantiate the logging stack and demands the license, even if no alarms are configured.
• Recipe data record logging. Recipe Views have an independent logging switch separate from HMI tag logging. Disabling tag logging does not remove the recipe log.
• Cross-version project copy. Projects created in V15.1 and imported into V16 will carry an IM folder that references V15.1 option packs. The cleanest remediation is to delete the IM folder immediately after import, before the first compile.
• Unified Comfort Panels. TP, KP, and Unified Comfort Panels run WinCC Unified, which uses the RT Professional logging model. The same dialog appears but is resolved by a different license. Confirm the device class before applying the fixes above.
• ALM service state. A stopped ALM service can produce a perpetual "not found" dialog even when the key is present. Open services.msc, locate Automation License Manager Service, and verify the state is Running.

Recommended Order of Operations

1. Confirm the exact TIA Portal version and HMI option pack version.
2. Inspect compile output for license requirement messages.
3. Disable Audit/GMP if not required for the application (or license it if required).
4. Delete all Data Logs and Alarm Logs not actively used.
5. Reset the Logged property on every alarm class.
6. Delete the IM folder and rebuild all.
7. Update ALM to the current release.
8. Recompile and re-download to the target.
9. Cycle power and confirm the dialog is gone.