Migrating WinCC 7.4 to 7.4 SP1 on Windows 10 LTSC 1809 Guide

Migrating WinCC V7.4 Clients to WinCC V7.4 SP1 on Windows 10 LTSC 1809

This reference documents the end-to-end migration of a SIMATIC WinCC V7.4 (Win32) HMI/SCADA installation from Windows 7 SP1 (32-bit or 64-bit) to Windows 10 LTSC 1809 (64-bit) using WinCC V7.4 SP1 as the destination version. It covers OS compatibility verification, redundant WinCC Server migration on Windows Server 2012 R2, license migration rules, WinCC Project Migrator workflow, SQL Server implications, and verification steps.

1. Why WinCC V7.4 SP1 Is the Correct Destination

Siemens releases WinCC operating-system support on a per-Service-Pack basis. The base WinCC V7.4 image carries the original OS lock list (Windows 7 SP1, Windows Server 2008 R2 SP1, Windows Server 2012, Windows 10 pre-1607 builds). Windows 10 LTSC 1809 (build 17763) is only listed as a supported client operating system starting with WinCC V7.4 SP1 (and the subsequent Updates 1…14).

The authoritative source is the Siemens Compatibility Tool for Automation and Drive Technology (Entry ID 64847781). Always consult it before any platform change because Siemens extends supported OS lists through Hotfix roll-ups (HF7, HF8, … HF14) without bumping the marketing version.

If the site standardises on LTSC 1809 (a common choice because LTSC branches receive 10 years of security updates), pinning WinCC to V7.4 SP1 with the appropriate Hotfix roll-up is the safest path that preserves existing V7.4 license investment and avoids a project migration to V7.5.

2. Prerequisites

1. OS baseline on every WinCC client: Windows 10 Enterprise LTSC 1809 (build 17763.x), 64-bit. Pro is technically listed but LTSC is preferred for industrial PCs (no Store app, no feature updates).
2. WinCC Server OS: Windows Server 2012 R2 (current) or Server 2016 / 2019 if you re-platform the server pair in the same outage. Do not run the WinCC Server service on a Windows 10 workstation even if the licence count fits; only the listed Server SKUs are supported.
3. SQL Server: WinCC V7.4 SP1 supports Microsoft SQL Server 2014 SP2 (64-bit) and SQL Server 2016. If you currently run SQL 2008 R2 or 2012, upgrade SQL — do not let it stay on an unsupported version after the migration.
4. .NET Framework: 4.6.2 minimum for WinCC V7.4 SP1; 4.7.2 recommended for LTSC 1809.
5. Domain membership: All WinCC Servers and Clients must remain in the same Active Directory domain or a domain with two-way transitive trust. Local-only accounts break WinCC redundancy and the WinCC User Administrator.
6. Backup of every WinCC project database (the *.MCF file plus the runtime archive databases) and the WinCC installation media (DVD or downloaded SIMATIC WinCC V7.4 SP1 setup).
7. Licence certificate of licence (CoL) for the existing V7.4 licence USB dongle or Software Passport; you will need it for the upgrade activation.
8. Outage window: For a redundant Server pair you can migrate one server at a time; the second server carries load while the first is re-imaged. Plan a 4–8 hour window per server plus 2 hours per client group.

3. Licensing: V7.4 → V7.4 SP1

Service Packs in the WinCC V7.x line do not require a new licence purchase. The existing V7.4 licences upgrade in place to V7.4 SP1 through the standard "upgrade" ordering data, which is a free entitlement, not a new product purchase. Refer to the Delivery Release for SIMATIC WinCC V7.4 (Entry ID 109483726), section 4. Ordering data → WinCC V7 Upgrade.

3.1 Re-hosting the licence

1. Install Automation Licence Manager V6.0 SP5 or later on the new Windows 10 LTSC 1809 client. ALM is shipped on the WinCC V7.4 SP1 DVD (Support folder) and from the Siemens support portal.
2. Return the licence from the old Windows 7 host using ALM → Licence → Return licence to licence storage. The dongle (parallel or USB) or Software Passport is then the only carrier of the entitlement.
3. On the new Windows 10 LTSC 1809 PC, plug in the dongle or point ALM at the Software Passport backup file (*.zip) and click Transfer licence.
4. Verify with almtstvw.exe that the WinCC RT/ES licences show as Locally valid.

4. Project Migration Strategy

WinCC project databases (*.MCF) are forward-compatible within V7.x using the bundled WinCC Project Migrator. The migrator is launched automatically the first time you open a V7.4 (or earlier) project in the V7.4 SP1 Configuration Studio. The official procedure is documented in "How do you migrate WinCC projects to new versions of WinCC from V4 to V7?" (Entry ID 44029132).

4.1 Pre-migration checklist

• Close the project in WinCC Explorer on every authoring station.
• Stop the WinCC Runtime on every server. On the redundant pair, take the standby server offline first.
• Stop the SQL Server (WINCC) service.
• Back up <Project>.MCF, GraCS\, Library\, PRT\, ScriptLib\, and the archive database folder.

4.2 Migration execution

1. Install WinCC V7.4 SP1 Configuration on the engineering station. Choose Custom install and keep the default SQL instance name WINCC to preserve ODBC DSN names.
2. Open WinCC Explorer → File → Open → select the V7.4 .MCF.
3. The Project Migrator prompts with Source version V7.4, Target V7.4 SP1, Continue?. Click Yes.
4. Confirm each sub-migrator (graphics, archives, alarms, scripts) reports OK.
5. Compile the OS project editor (Tools → Project Editor → Compile OS) to regenerate OS.BAT with the new SP1 paths.
6. Test-compile any C scripts (ANSI-C); V7.4 SP1 tightens the SDK headers and uninitialised variables become warnings that fail the compile gate.

4.3 Migration scope diagram

5. Step-by-Step Procedure: Client Workstations

1. Capture image. Document the existing Windows 7 install (drivers, applications, GPO settings, WinCC project path) using sysprep + a disk-imaging tool of choice (Acronis, ImageX, Veeam).
2. OS deployment. Deploy Windows 10 LTSC 1809 64-bit Enterprise. Apply the LTSC servicing branch so that feature updates are blocked, only security/monthly rollups are received.
3. Apply prerequisites. Install .NET Framework 4.7.2, MSMQ, DCOM, the Visual C++ 2015–2019 redistributable (x64 and x86), and the manufacturer's chipset/ethernet/graphics drivers.
4. Install ALM 6.0 SP5+.
5. Install WinCC V7.4 SP1 Runtime. Select WinCC RT Client or WinCC RT 2…12k PowerTags as appropriate.
6. Re-host the licence. Transfer the dongle/Software Passport to the new OS, verify with ALM Viewer.
7. Restore WinCC project. Either re-replicate the V7.4 SP1 project from the upgraded server, or run the Project Migrator locally on the Configuration Studio (only on clients that also host Configuration).
8. Validate WinCC startup. Launch WinCC Runtime and verify the connectivity to the WinCC Server pair (redundancy partner visible in WinCC Explorer → Redundancy → Status).

6. Step-by-Step Procedure: Redundant WinCC Server Pair

The classic WinCC redundancy model is two servers configured as partners: each runs WinCC Runtime independently and replicates the tag, alarm and archive state to the other via TCP/UDP on a dedicated partner channel (default port 80 or a configured partner port). Failover is application-level, not cluster-level.

1. Pre-flight. Confirm both servers are on the same WinCC V7.4 version and the same PowerTag count. Take a full image of both.
2. Migrate Server B (standby).
   • Stop WinCC Runtime on Server B.
   • Stop SQL Server (WINCC) on Server B.
   • Re-image to Server 2012 R2 / 2016 / 2019 (whichever your platform supports) + WinCC V7.4 SP1 + ALM.
   • Run the Project Migrator on Server B's project copy. Do not share .MCF files over the network while WinCC is running.
   • Configure redundancy partner IP, partner timeout (default 25 s), and partner watchdog port in WinCC Explorer → Redundancy.
   • Start SQL Server (WINCC).
   • Start WinCC Runtime on Server B. It will come up as Standby if Server A is still the master.
3. Cutover.
   • Stop WinCC Runtime on Server A.
   • Wait until Server B auto-promotes to Master (verify with Redundancy → Status).
   • Re-image Server A identically to Server B.
   • Restore Server A's project copy (Server B as the master).
   • Start Server A; it joins as Standby.
4. Post-cutover validation. Trigger a controlled failover by stopping WinCC Runtime on the master; standby should promote within partner_timeout seconds (default 25 s, configurable down to 5 s).

6.1 Redundancy architecture

7. SQL Server and Archive Considerations

WinCC V7.4 SP1 hard-codes its database connection to the WINCC SQL Server instance and to specific SQL versions. The supported combinations are:

Do not attach pre-existing archives (*.LDF / *.MDF) from a SQL 2008 R2 host to a SQL 2016 instance without first running DBCC CHECKDB and resizing the transaction log. The archive tag count limits, segment size and slow/fast ring buffers are unchanged across SP1, but the on-disk page format is not always backward-compatible between SQL 2014 and SQL 2017.

8. Verification Checklist

9. Troubleshooting Matrix

10. Roll-back Plan

Always retain the Windows 7 + WinCC V7.4 image for at least one validated production cycle after the migration. If SP1 causes a regression that cannot be resolved within the SLA, the procedure is:

1. Stop WinCC on both V7.4 SP1 servers.
2. Re-image both servers from the Windows 7 + V7.4 backup.
3. Restore the .MCF from the pre-migration backup.
4. Return the licences to the original ALM storage.
5. Restart the V7.4 service and verify redundancy.