Resolving WinCC Flexible SP1 OS Version Mismatch on MP370 Panels

The Siemens SIMATIC MP370 15" Touch HMI remains in operation across many process plants long after its primary engineering tool, WinCC Flexible, was succeeded by TIA Portal. When a fleet of MP370 panels is running OS image 7.1.0.0 and the engineering station has been upgraded to WinCC Flexible 2007 SP1 (or 2008 SP1), the project compile target moves to image 7.1.1.0. WinCC Flexible then refuses to transfer the project to the older panel, and the seemingly obvious workaround — forcing the project's OS version back to 7.1.0.0 — just disables the Transfer and Compile buttons. This article explains exactly why that happens, what the ES-to-panel image compatibility matrix looks like, and how to recover both the panels and the project without bricking a remote site.

Problem Statement: The 7.1.0.0 vs 7.1.1.0 Mismatch

When the WinCC Flexible ES version is later than the panel's runtime image, the Transfer dialog raises a hard error:

"The OS version of the target device (7.1.0.0) does not match the OS version of the project (7.1.1.0). The transfer cannot be started."

WinCC Flexible offers two remediations in the dialog:

1. Update the operating system on the panel.
2. Change the OS version of the project to match the panel.

For most sites the second option looks attractive — the project is already working, and an OS flash on a remote panel over Ethernet seems risky. The trap is that WinCC Flexible cannot compile a project to an OS image earlier than the one bundled with the installed ES. Setting the project's target back to 7.1.0.0 from an SP1 ES disables the Transfer and Compile functions because the ES does not own the earlier compiler and transfer toolkit. The only clean path back is to bring the panel forward to the project's OS image. The remainder of this article walks through the version matrix, the OS update procedure, and the post-update network reset that catches most engineers out.

Affected Hardware and Image Map

The MP370 family covers 12" and 15" Touch and Key variants, all running a Windows CE 5.0-based HMI runtime. The exact part number determines the image and licensing.

Common OS images shipped or flashed on these units:

• Image 7.0.0.0 — original WinCC Flexible 2005 Runtime.
• Image 7.0.1.0 — maintenance release with stability fixes.
• Image 7.1.0.0 — WinCC Flexible 2007 Runtime.
• Image 7.1.1.0 — WinCC Flexible 2007 SP1 / 2008 SP1 Runtime.

The 7.1.0.0 → 7.1.1.0 jump is the one most sites hit when they standardise on SP1 to pick up bug-fixes that affect Smart Access, audit trail, and recipe handling.

WinCC Flexible ES to Panel OS Compatibility

The compatibility matrix below is the single most important reference for this troubleshooting case. The last column is what makes the original workaround impossible.

The crucial column is the last one: WinCC Flexible has no down-compile path. There is no "compile to 7.1.0.0" checkbox, and editing the project file by hand is not supported. The only legitimate way to keep a 7.1.0.0 panel is to install WinCC Flexible 2007 (no service pack) on a separate ES and use it to maintain the older project, while your modern SP1 ES maintains everything else. For an eight-panel fleet this is rarely worth the second-license and second-VM overhead.

Why Forcing the Project Back to 7.1.0.0 Fails

The OS version field in the project is not just a label. It is a build-time constant that selects several runtime dependencies:

• The HMI Tags struct layout (pointer widths and enum sizes change between images).
• The Recipe export filter set (the .csv column order changed in 7.1.1.0).
• The Sm@rtAccess / Sm@rtService API version.
• The audit-trail XML schema (a root attribute was added in 7.1.1.0).
• The .fwx runtime container format and CRC seed.

When you edit the project OS version down to 7.1.0.0 from a 7.1.1.0 ES, the editor marks the project as "inconsistent against ES". The compiler refuses to run, and the Transfer dialog greys out. The buttons re-enable only when you re-align the OS version with the ES.

Error codes returned in the Output window of WinCC Flexible are:

Recommended Recovery: OS Update Over Ethernet

Updating the panel OS is the supported path and, in practice, faster than rebuilding the project on a legacy ES. WinCC Flexible ships with the OS image files inside the installation tree. The transfer can be done from a PC on the same Ethernet subnet; the panel does not need a serial cable, but you should be on-site for the first panel to confirm timing and recovery.

Prerequisites

• WinCC Flexible 2007 SP1 or later installed on the ES.
• ProSave installed (default in WinCC Flexible install).
• Ethernet connection between the ES and the panel (no firewall blocking TCP ports 102, 5001, 5002, 7000, 7001).
• Local admin on the ES.
• On-site presence for the first panel.
• The panel's current IP address, subnet mask, and gateway noted.
• A backup of the current HMI project file (.hmi / .fwx) on a USB stick or ProSave backup if possible.
• The new image .img file from the WinCC Flexible install (\Support\Images\MP370\).

Step-by-Step OS Update via WinCC Flexible

1. Start WinCC Flexible 2007 SP1 on the ES.
2. Open the project that targets 7.1.1.0.
3. From the menu choose Project → OS Update Wizard (or Tools → OS Update depending on the SP).
4. In the wizard, set the connection to Ethernet and enter the panel's IP address. Tick Set/reset Ethernet address of the target station and pre-fill the panel's current IP, subnet mask, and gateway so the panel is reachable after reboot.
5. Select the image file. For an MP370 15" Touch the file is MP370Touch_V7_1_1_0.img (or the equivalent in the \Support\Images directory).
6. Click Update OS. The transfer begins; a progress bar reports percent complete. The panel reboots automatically when the new image is written and re-initialised.
7. Wait for the panel to come back on the network (the loader screen stays for 30-90 seconds; the WinCC loader for another 60-120 seconds).
8. Reopen Transfer mode on the panel (the panel-side loader).
9. From the ES, choose Transfer → OS Update → OS Project and select the project's compiled .fwx runtime file.
10. Confirm transfer. The panel reboots into Runtime.

The whole per-panel flow on Ethernet takes 5-10 minutes including the post-update loader boot. Plan a full working day for a 24-panel site.

Step-by-Step OS Update via ProSave (Alternative)

When the project itself is not available (for example, you only have the panel and no .fwx), use ProSave directly. ProSave is more reliable for headless image loads and is the only supported tool for OS-only operations.

1. Launch ProSave from the Start menu (Siemens Automation → ProSave).
2. In General, select Device type: MP370 and Connection: Ethernet.
3. Click Settings... next to the IP and enter the panel IP.
4. Switch to the OS Update tab.
5. Tick Reset to factory settings only if you want to wipe the project; otherwise leave it unchecked.
6. Click Update OS and choose the .img file.
7. After completion, switch to the Backup/Restore tab to push a known-good project to the panel.
8. Reboot the panel from the loader.

The Hidden Step: Ethernet Reset After OS Update

A detail that consistently catches first-time operators is that the panel's Ethernet configuration is preserved across the OS update only if you explicitly told the wizard to "set/reset Ethernet address" with the same values. If you skipped that checkbox, the panel falls back to the default TCP/IP stack:

• IP address: 0.0.0.0 (DHCP disabled).
• Subnet mask: 0.0.0.0.
• Gateway: blank.
• MAC address: preserved.

At this point the panel is unreachable over Ethernet. Recovery procedure:

1. Connect a USB keyboard to the panel (the MP370 has a USB-A host port on the back).
2. Open Start → Settings → Control Panel → Network and Dial-up Connections.
3. Open DM9CE1 (the on-board Ethernet driver).
4. Set the IP address, subnet mask, and gateway manually.
5. Apply and reboot.

If a USB keyboard is not available on site, ProSave can rewrite the network configuration from a directly attached Ethernet peer using the Ethernet → IP Address page. You have to set up a /30 link between the ES and the panel, since the panel still has 0.0.0.0. Once the panel is back on the network, re-ping it and continue the project transfer.

ProSave Configuration Reference

The following ProSave parameters are the ones to record before and verify after the update. They live in ProSave.ini and can be scripted for fleet rollouts.

Why a Guy on Site Was the Real Save

If a panel is half-flashed and the loader is stuck, the only recovery paths are:

• Direct USB transfer of the image from a USB stick on the panel (the loader reads the \USB Storage\<image>.img path).
• Service console on the DB9 service port (115200 8N1) for diagnostic output and manual flash commands.
• 1:1 crossover Ethernet link and ProSave to push the image directly when the panel still has a partial stack.

Without one of these, a failed flash bricks the panel and the only recourse is RMA. For multi-panel fleet work, always send a technician to the first panel with:

• A laptop with WinCC Flexible and ProSave installed.
• A USB stick with the OS image, the compiled project, and the legacy 7.1.0.0 image as a fallback.
• A USB keyboard.
• A crossover Ethernet cable.
• A printed copy of the panel IP addressing sheet.

Best-Practice Path for an Eight-Panel Site

The pragmatic plan for a site with eight MP370 15" Touch panels on Ethernet:

1. Take a ProSave backup of every panel before touching anything. Save the .brf backups to a versioned folder on the ES.
2. Flash the first panel from the ES. Confirm runtime, tag updates, alarm handling, and operator login.
3. Roll out the remaining seven in batches of two to keep the engineering load manageable and to have a known-good panel to compare to.
4. After all panels are on 7.1.1.0, push the latest compiled project to each.
5. Update the version-control comment on the project to record the OS image change.

Time budget: ~30 minutes per panel once the procedure is proven, or about four hours total for the eight-panel site including documentation and a final walk-down with operations.

Comparison: OS Update vs Legacy ES

Audit Trail, Recipe, and License Considerations

Three follow-on items need attention after the OS update; missing any of them will surface as a runtime issue within a shift.

Audit trail. The XML schema changed between 7.1.0.0 and 7.1.1.0. A panel booting into 7.1.1.0 with a 7.1.0.0 audit database will display a schema warning at startup and refuse to write new entries until the audit database is archived and cleared. Use ProSave → Backup/Restore to archive the old database, then clear it from the panel-side control panel.

Recipes. The recipe CSV column order is identical in both images, but a 7.1.1.0 runtime that reads a 7.1.0.0 .csv will re-validate each row. This is fast for typical recipes (under 500 records) but can stall on the first screen open if the recipe has tens of thousands of entries. Plan a one-time recipe export/import if the project has hit that scale.

License transfer. The runtime license key is stored in a non-volatile partition that is preserved across the flash, so Sm@rtAccess and Sm@rtService entitlements do not need to be re-issued. They do, however, need to be re-activated if you ticked Reset to factory settings in the ProSave wizard. If the license key is lost, it must be recovered from the Siemens license database; budget 1-2 business days for Siemens support to re-issue.

Migration Note: MP370 to Comfort Panels

The MP370 has been superseded by the SIMATIC Comfort Panels (TP700, TP900, TP1200, TP1500, TP1900, TP2200) and, in turn, by the Unified Comfort Panels. The OS update procedure for Unified Comfort Panels is documented in the TIA Portal help at Updating the operating system via WinCC (TIA Portal). If you have the opportunity to replace rather than update, the Comfort Panels run TIA Portal projects natively, which removes the WinCC Flexible limitation entirely. For a fleet of eight MP370 panels, plan a phased migration: two panels per year over four years, paired with a TIA Portal engineering licence ramp-up.

For legacy MP370 sites, the broader Siemens automation support portal is the authoritative source for firmware images, ES service packs, and migration utilities: Siemens Industry Online Support.

Verification Checklist

After the OS update and project transfer, run the following checks before handing the panel back to operations:

• Panel boots into WinCC Flexible Runtime, not the loader.
• All configured screens render and navigate.
• User login and logout work.
• Tags read from the PLC match expected values.
• Alarms raise and acknowledge.
• Recipes read and write.
• Sm@rtAccess / Sm@rtService connection (if used) is reachable.
• Audit trail records a login event.
• Date and time are correct (the panel RTC retains time across the flash).
• Ethernet ping from the ES to the panel is < 1 ms on a /24 LAN.
• The 24 V DC supply voltage at the panel terminals is within tolerance (19.2-28.8 V).
• The project CRC, displayed in the project information screen, matches the source .fwx.

Troubleshooting Matrix

Field-Proven Caveats

• Do not interrupt power during the OS flash. The flash partition write is atomic only at the block level; a mid-write brown-out leaves the loader running but the runtime missing. Recovery requires a USB stick with the image in \USB Storage\.
• Tick "set/reset Ethernet" every time. Skipping it has stranded more remote panels than any other setting in WinCC Flexible.
• Re-issue the project CRC, not just the project file. The runtime stamps the CRC on first boot; if you re-transfer the same .fwx without re-compiling, the audit trail will show no change and the operators will not realise the panel is now running a new build.
• Check the panel date format after the flash. The regional setting is preserved but the locale string handling for audit trail export changed subtly between 7.1.0.0 and 7.1.1.0. Audit exports in DD/MM/YYYY that were generated by 7.1.0.0 can confuse the 7.1.1.0 audit viewer.
• Plan a 5% rework rate. On a 20-panel roll-out, expect one panel to need a manual recovery (USB stick or service console). That is the budget the on-site technician is there for.