WinCC V7 SP1 RC Runtime License Error: Causes and Fixes

Problem Overview

After installing SIMATIC WinCC V7.0 SP1 with the RC 512 Power Tags package (order number 6AV6381-2BN07-0AX0) and activating a project in Runtime, operators encounter a licensing/runtime error dialog or the system refuses to remain in Runtime. Engineers commonly misread the order code and assume they have purchased a 512 Power Tag license, when in fact the package provides 256 external tags (Power Tags) with 512 archive tags allocated to Tag Logging. The error is typically raised not by a defective key, but by:

1. Exceeding the actual licensed Power Tag count.
2. Selecting an unsupported project type (for example, Multi-User) for a Single-User license.
3. Loss of license data from the Automation License Manager.
4. Wrong subset of license keys migrated off the USB stick.

Order Code Decoding: What RC 512 Actually Means

Siemens uses a fixed MLFB (machine-readable product designation) for WinCC V7 packages. The relevant decoding for the order 6AV6381-2BN07-0AX0 is:

The numeric suffix appended to RC in product marketing material refers to the archive tag limit, not the Power Tag count. The actual Power Tag limit for 6AV6381-2BN07-0AX0 is 256 Power Tags. The corresponding archive tag allowance is 512.

How WinCC V7 Counts Tags

Understanding the three tag categories is critical to interpreting any license error:

• Power Tags (External Tags): Each variable exchanged between WinCC and a PLC (via S7, OPC, Modbus, etc.). 1 PLC address = 1 Power Tag regardless of bit width. Struct members count individually. This is the value that must be ≤ the licensed limit.
• Internal Tags: Not Power Tags; unlimited in V7.
• Archive Tags: Tags configured under Tag Logging for historian/alarm archival. Counted against the archive tag limit, not the Power Tag limit.
• Alarm Tags: Counted separately under Bit Message / Analog Alarm limits defined by the project size.

To confirm the live count in the running project, look at the WinCC Explorer status bar (bottom right):

1. Open WinCC Explorer.
2. Do not close it; the status pane continuously updates.
3. Read the External Tags counter; this is the Power Tag usage.
4. Right-click the Tag Management editor to see full per-driver detail.

Formula for determining whether a project fits the license:

If the count exceeds 256 on an RC 256 license, Runtime cannot start in any project type.

Project Type: Single-User vs Multi-User vs Client

The most common root cause of a WinCC V7 SP1 RC runtime error when the Power Tag count is correct is the project type selection in WinCC Explorer during project creation.

If you create the project as Multi-User but only hold an RC license, the Server subsystem requires an additional WinCC Server authorization. WinCC will raise a license error at Runtime activation and may revert to a degraded state. The fix in the source case was to convert the project to a Single-User Project via:

1. Open WinCC Explorer → right-click the project root → Properties.
2. Select the Type tab.
3. Change Multi-User to Single-User.
4. Confirm the warning dialog about project restructuring.
5. Recompile the OS (Graphics) and Tag Logging DB.
6. Activate Runtime.

Automation License Manager Workflow

Siemens licenses for WinCC V7 are stored on a USB License Stick (red ALM key) or a hardlock. The Automation License Manager (ALM) reads the key on startup. Common failures occur when:

• The USB key is removed or replaced with a key for another product.
• Multiple license packages are present on one stick and the wrong one is active.
• The ALM service (almservice) has not started.
• The license database on the hard disk is corrupted.

Recommended License Migration Procedure

1. Insert the original USB license stick containing the WinCC RC 256 license.
2. Open Automation License Manager from the Windows Start menu.
3. Select the source stick → right-click → Transfer License.
4. Move all licenses to a clean local C: drive target (C:\ProgramData\Siemens\Automation\License\Local or similar).
5. Re-insert the USB stick; transfer only the WinCC licenses back:

• WinCC RT (Runtime)
• WinCC Configuration
• WinCC Option packages actually used (e.g., User Archive, WebNavigator)

Do not migrate these unused/incompatible keys (which can confuse the manager or cause checksum errors):

• S5 Ethernet Layer 4
• 505 Ethernet Layer 4
• Profibus FMS
• 505 TCP/IP

6. Restart the almservice from Services snap-in (services.msc).
7. Open WinCC Explorer and start Runtime.

Verification of License Visibility

From WinCC Explorer menu bar: Help → About → Installed Licenses. Confirm:

Common Runtime Error Patterns

The licensing reminder dialog appearing every 10 minutes indicates unlicensed mode and is a documented behavior in PC-based HMI Runtime when the key is missing or invalid. See Licensing WinCC Runtime on PC-based HMI devices (TIA Portal) for the parallel TIA Portal flow.

Step-by-Step Recovery Procedure

Use this ordered procedure when Runtime fails after a fresh install or after migrating licenses.

1. Verify the project type. WinCC Explorer → project root → Properties → Type tab. Set to Single-User Project if you hold only an RC license.
2. Verify Power Tag count. Compare status bar external-tag count to the licensed Power Tag allowance. Remove tags or upgrade license to match.
3. Verify ALM service. Run services.msc and confirm Automation License Manager Service is Started and Automatic.
4. Clean license state. Stop almservice; navigate to %ProgramData%\Siemens\Automation\License; back up and remove the *.lic and *.log files; restart the service.
5. Re-migrate the correct licenses. Transfer only WinCC RT + CS + Power Tag entitlement from the USB stick.
6. Reinstall if necessary. If licenses still do not appear, run the WinCC V7 SP1 setup with Repair mode and ensure both Configuration and Runtime are checked.
7. Recompile and restart. Open WinCC Explorer; right-click → Recompile All. Then activate Runtime.
8. Validate stability. Let Runtime run for 30 minutes and confirm no license reminder dialogs appear.

Upgrading or Replacing a Defective Key

If the USB license stick physically fails or the license data is corrupted, the recovery path is:

1. Generate a License Key Request from Automation License Manager → Help → License Key Request.
2. Provide the License Number, Part No. (e.g., S79220-B10U-02), and Serial Number (e.g., SVPA41009592) to Siemens Customer Support via the official support portal.
3. Siemens issues a new License Key File (.lic) bound to a new USB stick or host fingerprint.
4. Import the new key via ALM and re-verify WinCC Explorer → Help → About.

Preventive Maintenance Checklist

• Document the exact MLFB, Power Tag count, archive tag count, and license number in the project documentation folder.
• Take an annual backup of %ProgramData%\Siemens\Automation\License and the USB license stick contents.
• Verify Windows updates do not disable almservice by checking the service's Startup Type after major patches.
• Avoid installing third-party dongle drivers that interfere with the ALM USB stack.
• Before any project migration from V7 to TIA Portal (WinCC Professional), evaluate license reallocation. TIA Portal uses SIMATIC WinCC Runtime Professional V21 licensing model which differs from V7.

When to Escalate to Siemens Support

If the Automation License Manager does not display the WinCC entries after the recovery procedure, escalate to Siemens Industrial Online Support with the following data:

• Order number, license number, part number, serial number
• WinCC V7 version (e.g., 7.0.1.0) and SP level
• ALM version (Help → About)
• Screenshot of Installed Licenses tab
• Screenshot of Runtime activation error
• Project type and Power Tag count

Do not post this information on third-party forums; use Siemens' official support channel for license-related issues to avoid exposing keys publicly.

Field-Validated Summary

The fastest path to resolution in 95% of "WinCC V7 SP1 RC Runtime license error" cases is to first verify the project type (must match license class) and the Power Tag count (must be within licensed allowance). License file transfers via ALM are secondary. Confirming the MLFB to Power Tag mapping — for example, 6AV6381-2BN07-0AX0 equals 256 Power Tags — prevents the recurring confusion between "RC 256" (Power Tag count) and "RC 512" (archive tag count). Once project type is correct and the tag count is within budget, the Automation License Manager displays the entitlements and Runtime starts without dialog interruption.

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