How to Troubleshoot WinCC Runtime Switching to DEMO Mode on Activation in SIMATIC PCS 7

WinCC Runtime switches to DEMO mode upon activation when a valid base Runtime Process Object (PO) license is missing, version-mismatched, or exceeded, even if add-on licenses like Tag Logging Archives are fully present. Archive licenses (e.g., 1500 or 3000 Archive Tags) license data historian capacity but do not grant permission to execute WinCC Runtime itself. Resolving DEMO mode requires checking the Automation License Manager (ALM) for missing base licenses, using the WinCC License Analysis tray utility to identify the exact missing key, and installing the correct PCS 7 OS Software Single Station or Server license.

Understanding DEMO Mode Triggers in WinCC and PCS 7

When activating a SIMATIC WinCC or PCS 7 OS project, operators and engineers may encounter a warning banner or popup stating: 'License has expired! Please Obtain a Valid License' or notice that the lower status bar switches to 'DEMO' mode. After a trial timeout period, runtime functionality may be restricted or periodically interrupted.

This occurs when the Automation License Manager (ALM) runtime validation service fails to find an authorized, non-expired license key matching the activated software configuration.

Common root causes include:
1. Confusing Add-On Licenses with Base Licenses: An engineer may install an archive license (e.g., WinCC / Archive 3000 Tags) believing it covers runtime execution, whereas a base WinCC Runtime or PCS 7 OS Software Single Station license is also strictly required.
2. Version Mismatch: Running PCS 7 V8.1 or V8.2 with legacy licenses from PCS 7 V7.1 or V8.0. Licenses are version-specific unless an upgrade license key has been applied.
3. Station Role Conflict: Installing an OS Client license on an Engineering Station or Single Station where an OS Server or Single Station license is required.
4. License Key Expiration: The system was operating on a 14-day or 21-day temporary Trial License that has reached its expiration date.

Archive Licenses vs Base Runtime Process Object Licenses

In Siemens industrial automation systems, software licensing separates base system operation from functional capacity expansions:

Base Runtime Licensing

To execute WinCC Runtime, a node must have a base execution license:
* In standard WinCC: SIMATIC WinCC RT (128, 512, 2048, 8k, 65k) tags.
* In SIMATIC PCS 7: SIMATIC PCS 7 OS Software Single Station (e.g., MLFB 6ES7658-2CX58-0YB0) or SIMATIC PCS 7 OS Software Server (e.g., MLFB 6ES7658-2BA58-0YB0), which includes base Process Objects (e.g., 250 POs).

Archive Licensing

The WinCC / Archive license (e.g., 1500, 3000, 5000, or 10000 archive variables) is strictly an optional capacity package. It permits the Tag Logging system to record historical analog and binary trends beyond the default 512 archive variables included with the base product. It possesses zero execution rights for the graphical runtime engine.

Diagnostic Workflow via WinCC License Analysis and ALM

To pinpoint the missing license key without guessing, follow this diagnostic workflow:

Step 1: Use WinCC License Analysis

While WinCC Runtime is active (or attempting activation), locate the blue WinCC icon in the Windows notification tray (taskbar bottom-right).
Right-click the icon labeled SIMATIC WinCC RT and select WinCC License Analysis.
The utility displays a detailed list of all requested license components alongside their current authorization status:
* Missing: Indicates an essential component has no valid key in ALM.
* Demo: Identifies components currently running under evaluation grace periods.
* Count Exceeded: Identifies whether configured Process Objects or archive variables exceed installed licenses.

Step 2: Inspect Automation License Manager (ALM)

Open Automation License Manager (Start -> Siemens Automation -> Automation License Manager).
Select drive C: (or the drive hosting licenses) under Installed Licenses.
Switch the view mode via View -> Missing License Keys.
Check if any license shows a status of 'Corrupted', 'Expired', or 'Trial'.
Verify that the license version exactly matches the installed PCS 7 / WinCC version (e.g., Version 8.1 vs Version 8.2).

Licensing Architecture and Capability Matrix

The following table outlines the required licenses for typical PCS 7 station roles and their functional boundaries:

Station Architecture RoleRequired Base LicenseTypical MLFB ExampleIncluded CapacityRequired Add-on for TrendingOS Single Station (PCS 7)OS Software Single Station V8.26ES7658-2CX28-0YB0250 OS RT POs, 512 Archive TagsWinCC Archive (if >512 tags)OS Server (PCS 7)OS Software Server V8.26ES7658-2BA28-0YB0250 OS RT POs, 512 Archive TagsWinCC Archive (if >512 tags)OS Client (PCS 7)OS Software Client V8.26ES7658-2CX28-0YB5Client Runtime AccessNone (archives hosted on server)Engineering Station (ES)PCS 7 Engineering V8.26ES7658-5AX28-0YB5AS/OS Engineering POsNot applicable for engineeringArchive ExpansionWinCC / Archive 30006AV6371-1DQ17-3AX03,000 Historical Archive TagsRequires Base RT License

Validate final license requirements against Siemens delivery notes and consult an authorized Siemens distributor for official quotation.

Verification

To verify that licensing is valid and DEMO mode has been resolved:
1. Transfer the correct base license key onto the local machine using Automation License Manager.
2. In WinCC Explorer, stop Runtime if running and reactivate the project.
3. Observe the bottom status bar in WinCC Runtime: verify that the text 'DEMO' is replaced by normal system status indications.
4. Right-click the taskbar tray icon and run WinCC License Analysis; confirm that all subsystems report 'OK' or 'Licensed' with zero missing keys.
5. In ALM, execute License Key -> Check on the installed keys to verify cryptographic integrity.

Limitations and Operational Precautions

Running WinCC in DEMO mode in production environments is dangerous: after the trial period elapses, the runtime engine terminates or locks operator control screens.
Archive licenses cannot be combined additively across different major versions; upgrading WinCC requires an corresponding archive upgrade license.
Virtualized systems (VMware ESXi) must have static network MAC addresses and fixed drive UUIDs, or ALM may invalidate installed floating licenses.
Do not store license keys on network shares or USB drives during runtime; transfer them permanently to a local hard drive partition.

Engineer FAQ

Can I run WinCC Runtime if my archive tag count exceeds my license limit?

Yes, but WinCC will enter DEMO mode for the Tag Logging archive component, displaying periodic license popups. Historical logging for tags beyond the licensed limit may be discarded.

Why did my license expire if purchase documents show no expiration date?

Permanent licenses (Single License / Floating License) never expire. If an expiration warning appears, you are running an emergency Trial License (valid for 14 or 21 days), or the permanent key was moved or corrupted.

How do I upgrade a V7.x license to V8.x?

You must purchase an Upgrade License package (e.g., Upgrade Single Station V7.x to V8.x) and use ALM's 'Upgrade' function to transform the legacy key into the new version key.