Resolving Missing WinCC Server and Single Station Licenses in PCS 7 V9.0

When launching WinCC on an Operator Station in SIMATIC PCS 7 V9.0 and receiving license fault messages requesting 'PCS7 OS Single Station Basic' and 'PCS7 OS Server Basic', the WinCC project configuration or station topology in SIMATIC Manager does not match the licenses installed in Automation License Manager. In a multi-user client-server architecture, each redundant server requires an 'OS Server Basic' license (6ES7658-2BA58-0YB0), a 'WinCC Redundancy' license, and booked OS RT PO licenses; it does NOT require an 'OS Single Station Basic' license. If WinCC requests both, the station was erroneously inserted as an OS Single Station in the project tree or the project type in WinCC Explorer properties is mismatched.

Distinguishing OS Single Station vs OS Server Architectures

In SIMATIC PCS 7 V9.0 (running WinCC V7.4 SP1), Operator Stations are engineered according to two distinct physical topologies:

OS Single Station (OS Einzelplatzsystem): A standalone workstation that executes WinCC Runtime, maintains its own local database, and interfaces directly with AS controllers. It is designed for small installations without dedicated client machines and is licensed via the 'SIMATIC PCS 7 OS Single Station Basic' license.
OS Server (OS Mehrplatzsystem / Server-Client): A multi-user architecture where dedicated redundant OS Servers manage process acquisition, historical logging, and alarm databases, while distributed OS Clients provide visualization for plant operators. OS Servers are licensed via the 'SIMATIC PCS 7 OS Server Basic' license.

Why WinCC Requests Conflicting Basic Licenses

A common configuration pitfall occurs when an engineer configures an OS object in SIMATIC Manager as an 'OS Single Station' and subsequently assigns a redundant partner, or sets the computer type to 'Server' in WinCC Explorer. This creates an architectural conflict:

Project Type Inconsistency: WinCC detects redundant partner settings (demanding an OS Server license) while the project header retains the Single Station definition (demanding a Single Station license).
Missing Redundancy and PO Licenses: WinCC Runtime audits installed license keys upon startup. If the server is configured with an OS Single Station license but detects client connections or redundancy scripts, it issues missing license popups for OS Server Basic, WinCC Redundancy, and OS RT PO.
Tag Logging Archive License Exceeded: If the project archives exceed 512 process tags, WinCC additionally triggers the 'Archive' license warning.

Mandatory License Schedule for Redundant OS Servers

To eliminate license warnings in a redundant OS Server environment, verify that each physical server node holds the following exact license complement in Automation License Manager (ALM):

Base Server License: SIMATIC PCS 7 OS Server Basic V9.0 (installed on both Server A and Server B).
Redundancy Option: SIMATIC PCS 7 WinCC Redundancy V9.0 (installed on both Server A and Server B).
Booked OS Process Objects: SIMATIC PCS 7 OS RT PO license packages matching total booked technological objects.
Archive Expansion: SIMATIC PCS 7 OS Archive license (if archiving more than 512 tags).

Equipment Schedule and License Ordering Reference

The table below details the official Siemens license packages required for PCS 7 V9.0 Operator Stations.

Software License PackageMLFB / Order NumberLicense CategoryRequired Deployment ScopeSIMATIC PCS 7 OS Server Basic V9.06ES7658-2BA58-0YB0Server Runtime License1 license per OS Server in client-server architectureSIMATIC PCS 7 OS Single Station Basic V9.06ES7658-2AA58-0YB0Single Station License1 license per standalone single-station PCSIMATIC PCS 7 WinCC Redundancy V9.06ES7658-2CX58-0YB0Redundancy Option License1 license per redundant server (both Server A and B)SIMATIC PCS 7 OS RT PO (100 PO)6ES7658-2XA00-0YB0Process Object LicenseExpands OS runtime capacity by 100 process objectsSIMATIC PCS 7 OS Archive (1500 Tags)6ES7658-2FA58-0YB0Tag Logging OptionExpands historical tag logging beyond 512 base tags

[!IMPORTANT]
Commercial Accuracy and Procurement Disclaimer: Final licensing counts and MLFB selections must be verified against > official Siemens product documentation and quotation from an authorized distributor. Configuration tools such as CDT serve > as planning aids and do not establish contractually binding license entitlements.

Step-by-Step Procedure to Reconcile OS Project Topology

Follow this procedure to correct OS project topology and resolve conflicting license demands:

Check Station Configuration in SIMATIC Manager:
- In Component View, expand the PC Station representing the OS Server.
- Verify the object type: ensure it is configured as a WinCC Appl. (Server Application), not a WinCC Appl. (Single Station).
- If incorrectly configured as a Single Station, create a new PC Station with WinCC Appl., copy the charts and pictures, and recompile.
Check WinCC Explorer Project Properties:
- Open WinCC Explorer on the OS Server.
- Right-click project name -> Properties.
- In the General tab, verify that Type: is set to Multi-User Project (not Single-User Project).
Verify License Installation in ALM:
- Open Automation License Manager.
- Confirm that PCS 7 OS Server Basic V9.0 is installed on drive C:.
- Confirm that PCS 7 WinCC Redundancy and sufficient OS RT PO licenses are present.
- Ensure that obsolete OS Single Station Basic trial keys are removed or uninstalled to prevent license manager conflicts.
Recompile OS and Download:
- Run a full OS Compilation from SIMATIC Manager.
- Download the project to both Primary and Standby OS Servers.

Verification

Verify license resolution through the following checks:
1. Launch WinCC Runtime on the OS Server: verify that runtime activates smoothly without 'Required licenses' popup dialogs.
2. In Automation License Manager, select View -> License keys: verify that all required licenses show status 'OK' with green icons.
3. Open the Windows Event Viewer: verify that no Siemens License Manager warning events (Event ID 1000) are recorded.
4. Check WinCC Redundancy: confirm that internal tag @RM_MASTER and @RM_SERVER_STATE indicate healthy synchronization.

Limitations and Operational Precautions

Operating WinCC without required licenses causes the runtime system to enter 'Demo Mode'. In Demo Mode, WinCC displays persistent license warning banners and will automatically shut down after several hours of operation. Never run production facilities under missing license conditions. Furthermore, in redundant server pairs, always license both servers identically to prevent failover aborts.

Engineer FAQ

Why does WinCC ask for an OS Server license if I have no clients?

If you configured a redundant partner server in WinCC Redundancy, WinCC automatically operates in Server-Client mode (multi-user), requiring the OS Server Basic and Redundancy licenses regardless of whether clients are connected.

How many process tags are included in the base OS Server license?

The base OS Server license includes 512 archive tags for Tag Logging. Archiving more than 512 process tags requires additional OS Archive license packages (e.g., 1500, 5000, or 10000 archive tags).

Can I transfer an OS Single Station license to an OS Server?

No. OS Single Station Basic and OS Server Basic are distinct software entitlements with different MLFB numbers and pricing structures; upgrading requires purchasing an official PowerPack upgrade license.