Troubleshooting WinCC Flexible 2008 SP3 Runtime Auto-Exit on SIMATIC MP277 Touch Panels

1. Problem Scope and Operating Conditions

The failure mode described in the field is a specific, repeatable pattern: a project compiled in WinCC flexible 2008 SP3 (build 5.4.x) is downloaded to an MP277 Touch panel (or to the matching RT simulator), the runtime boots, all configured startup screens render normally, communication tags begin to update, and then 10 to 15 seconds after the HMI boot sequence completes, the runtime process terminates and the panel drops back to the Transfer utility. The PLC connection is not in run-stop; tags were updating correctly up to the moment of termination, which rules out a PLC-side fault such as a PROFIBUS slave failure or an S7 CPU going to stop.

Three layers must be evaluated whenever this symptom appears:

1. Project integrity on the engineering PC – corrupted area pointer configuration, missing PLC handle, or mismatched Project ID.
2. Runtime residue on the engineering PC – orphaned processes from a previous WinCC flexible RT session that was terminated through Windows Task Manager instead of the standard close command, which trips the internal initialization guard and raises message 140012.
3. Panel-side image integrity – damaged transfer block on the internal flash, mixed versions between the runtime kernel and the loaded project, or an incomplete OS image.

2. Affected Hardware, Firmware, and Software

The reported symptom maps to the following Siemens product and software combination. Versions are the ones the field engineer must verify in Device Properties in WinCC flexible before applying the corrective steps below.

The reference runtime documentation is the SIMATIC HMI WinCC flexible 2008 Runtime User Manual, which describes the runtime lifecycle, the area pointer mechanism, and the meaning of the runtime system alarms in section 5.4 ("Settings of the Runtime software") and the alarm appendix.

3. Root Cause Analysis

Five root causes are documented by Siemens for the "runtime starts then auto-exits" pattern on the MP277 / WinCC flexible 2008 SP3 combination. The first three account for the vast majority of field occurrences.

3.1 Project-ID Area Pointer Mismatch

The most common root cause is a non-zero, non-matching Project ID area pointer. The Project ID is an optional area pointer configured in WinCC flexible under Connections > Area Pointers. The HMI compares the value at the configured PLC word address with the value stored in the HMI project on every startup. If the values do not match, the HMI logs a configuration error, raises a connection-loss event, and exits runtime. This is the intended Siemens safety behavior: it prevents an HMI from running a project that is out of sync with the controlling PLC, but it also causes the auto-exit symptom if the field engineer enables the pointer, downloads a project, and never writes the expected value into the PLC DB at the configured address.

3.2 Task Manager Termination Residue (Message 140012)

The WinCC flexible Runtime User Manual documents message 140012 as an initialization error raised "e.g. when WinCC flexible Runtime was closed in Task Manager". When a previous RT session is killed through taskkill /F or by ending the process in Task Manager, the runtime writes an internal lock file. On the next RT start, the guard detects the lock, raises 140012, and aborts the load. The clean path is to close runtime through the standard exit button in the project. A second symptom of this root cause is that the simulator reproduces the fault on the engineering PC, which isolates the problem away from the panel hardware.

3.3 Corrupted Transfer Block on the Panel

If a transfer is interrupted at exactly the wrong moment (loss of power, USB cable removed, ES crash), the internal flash on the MP277 may contain an incomplete project block. On the next boot the loader detects an invalid CRC and refuses to start the runtime, falling back to the Transfer screen. WinCC flexible 2008 SP3 reports this as "Project not found on device" in the transfer log, and the panel shows "Connecting to host..." indefinitely.

3.4 Mixed Panel Family Image

An OS image generated for a different Siemens panel family (e.g. an MP370 image) is not compatible with the MP277 loader. Runtime will start, immediately fail the version check, and exit. The fix is to reflash the correct image using ProSave. Always verify the panel's MLFB in WinCC flexible under Device > Target matches the order number on the rating plate.

3.5 Transfer Channel or Boot Block Corruption

The MP277 boots from an internal loader that reads the project from a hidden partition. If the boot block itself becomes damaged, every project – even a known-good one – will be rejected. This is the worst-case scenario and requires a ProSave image restore.

4. Symptom Differentiation Matrix

Use the table below to map the observed behavior to a root cause before applying the fix. Do not skip directly to OS restore; in many cases the fix is a single check mark in the project.

5. Pre-Diagnostic Checklist

Complete these checks before changing any project settings. Each one rules in or out a category of causes and is faster than rebuilding the project from scratch.

1. Open Project > Device Properties > Target in WinCC flexible 2008 SP3 and confirm the panel order number matches the rating plate on the MP277.
2. Verify the WinCC flexible build number under Help > About. The build on the ES must match the runtime build installed on the PC and must be compatible with the panel image (SP3 is required for MP277 8"/10" Touch running WinCE 6.0).
3. Open Connections > Area Pointers. Note whether the Project ID row has a tick and which PLC word address is configured. Most auto-built projects from older versions leave this disabled – confirm before assuming the value is set.
4. Open Windows Task Manager and end every WinCCflexRT.exe and CCLoad.exe process. If these processes reappear after a fresh simulator start, the residue root cause is confirmed.
5. Re-check the transfer cable. PROFINET (Ethernet) transfers require the panel's transfer mode to be active (the loader shows "Transfer" on the status bar before the project is sent).
6. Capture the alarm view. Before runtime exits, the alarm line or alarm window will show message 140012 or a "Project ID mismatch" entry. Screenshot the alarm to confirm the cause.

6. Resolution Path A – Project-ID Area Pointer Configuration

This is the most common fix and should be attempted first.

6.1 Disable the Project ID

1. In the WinCC flexible 2008 SP3 project, open Project > Connections > Area Pointers.
2. Click the Project ID row, then click Configure....
3. Uncheck Active. Click OK.
4. Recompile the project (Project > Compiler > All) and transfer to the panel.

6.2 Enable the Project ID and Match the PLC Value

Disabling the Project ID is the fastest path back to a running system but loses the out-of-sync protection. In a production environment, write the expected value into the configured PLC word address instead.

1. Pick a unique integer, e.g. 1, 2, or the current build number. The configured word must be in a retentive DB in the S7 CPU.
2. In STEP 7 / TIA Portal, write the value to the configured address in OB100 (warm restart) so the value is present on every CPU restart.
3. In WinCC flexible, open Project > Connections > Area Pointers > Project ID, enable the pointer, and enter the same number in the Project ID field shown in the project properties screenshot in the Runtime User Manual.
4. Recompile and transfer.

6.3 Verification

Power-cycle the panel. Runtime should stay up indefinitely and never drop to the transfer screen. To confirm the value is being read, change the value in the PLC online and observe whether runtime exits (it should). Restore the value, runtime should not auto-exit again.

7. Resolution Path B – Task Manager Residue (Message 140012)

Symptom: the simulator on the engineering PC also auto-exits, which means the project file is the issue, not the panel. After killing a previous WinCC flexible RT session through Task Manager, the runtime writes a lock file in the user profile. The lock is read on the next RT start; if it does not match, message 140012 fires and runtime aborts.

7.1 Clean the RT State

1. Close WinCC flexible ES completely.
2. Open Task Manager, end every WinCCflexRT.exe, CCLoad.exe, and CCAlg.exe process.
3. Delete the file %LOCALAPPDATA%\Siemens\WinCC flexible 2008\RT\lock if present. The exact path varies by Windows version; search the user profile for any file named *.lck or RT.lock created by Siemens Automation.
4. Restart WinCC flexible 2008 SP3 and start the RT simulator. Confirm the auto-exit is gone on a clean environment.

7.2 Always Exit Runtime Cleanly

Configure a dedicated exit button on the home screen that calls the system function StopRuntime and then closes the application. Never end the process through Task Manager – this is the upstream cause of the 140012 lock condition documented in the Runtime User Manual.

8. Resolution Path C – Corrupted Transfer Block / Project Rebuild

Symptom: the auto-exit happens only after a transfer, not when running the simulator on a clean PC. The compiled RT file on the engineering PC is fine, but the file written to the panel flash is damaged.

8.1 Reset the Transfer State on the Panel

1. Power on the panel, immediately tap the Transfer button on the loader screen to put it into transfer mode.
2. In WinCC flexible, choose Project > Transfer > Transfer to Device.
3. Check the box Overwrite in the transfer dialog and clear the option to keep the existing project – a full overwrite forces a clean block write.
4. Wait for the transfer to complete and the panel to reboot on its own. Do not interrupt the cycle.

8.2 Rebuild the Project from a Known-Good Source

If the problem persists after a clean overwrite, the project file (.hmi) itself is the problem. Use the field-tested recovery path: create a new WinCC flexible 2008 SP3 project targeting the same MP277 MLFB, copy screens and tags one at a time from the suspect project, and transfer the new build. This is the path the field engineer reported as the actual fix in the field report. To prevent the issue from recurring, do not enable the Project ID area pointer on the new project unless the matching PLC value is also being written.

9. Resolution Path D – OS Image Recovery with ProSave

If the panel still drops to "Connecting to host..." after a clean transfer of a known-good project, the OS image is damaged. Recover it with ProSave, the Siemens service tool bundled with WinCC flexible 2008 SP3 and also available separately on the Siemens Industry Online Support portal.

9.1 Restore an MP277 Image via Ethernet

1. Connect the engineering PC directly to the MP277 with a crossover or patch cable. Set the PC NIC to a fixed address in the 192.168.1.x range (the panel defaults to 192.168.1.2 on the PN/IE interface).
2. Boot the panel into Transfer mode.
3. Open ProSave and choose Panel > Restore > Restore image.
4. Browse to the matching MP277 image (.img) shipped with the WinCC flexible 2008 SP3 installation. Use the image whose order number matches the rating plate; do not substitute an MP370 / MP377 image.
5. Click Restore. The panel will reboot twice during the process; do not disconnect power.
6. After the second reboot, transfer the project again.

9.2 Restore an MP277 Image via USB / MPI

For panels without a working Ethernet interface, use the RS-422 / MPI port with the appropriate PC adapter (PC-Adapter USB A2). In ProSave select the PC-Adapter as the connection and follow the same restore path. The transfer is slower; allow 20 to 45 minutes for an 8" panel.

10. Verification Procedure

After any of the four resolution paths, run this checklist before closing the call. All three items must be green.

1. 30-Minute Soak Test – Let runtime run undisturbed for 30 minutes with a live PLC connection. Cycle the values of a few tags to confirm the HMI tag update is active. The original failure manifested at 10 to 15 seconds, so a clean 30-minute run gives a strong margin.
2. PLC Restart Test – Stop and restart the S7 CPU from STEP 7. Runtime on the panel should remain up (the connection is re-established automatically) and must not drop to the transfer screen. If it does, the Project ID pointer is misconfigured (see Section 6).
3. Power-Cycle Test – Power down the panel for 60 seconds, then power up. Runtime must boot and stay up.

11. Preventive Configuration Best Practices

• Lock the WinCC flexible build. Document the exact build (5.4.0.x) of WinCC flexible 2008 SP3 used for the project. Different SP3 patches can produce different RT binaries even with the same source file.
• Pin the MLFB. The Device Properties must show the exact panel order number. If a panel is replaced in the field, the project must be re-targeted and re-transferred, not just re-compiled.
• Avoid the Project ID on simple systems. If a single S7 CPU is the only PLC, the Project ID is rarely worth the maintenance cost. Leave it disabled.
• Use StopRuntime buttons. Always exit runtime through a configured button calling StopRuntime. Never close the RT process from Task Manager; this is the documented trigger for the 140012 residue condition.
• Keep one ProSave image on the engineering PC. For every panel on site, archive the matching .img file. This shortens a future restore from hours to minutes.
• Centralize the panel firmware version. When the engineering team has several MP277 panels, do not mix WinCE 5.0 and WinCE 6.0 images. The two images are not interchangeable, and cross-flashing a panel with the wrong one will produce exactly the auto-exit symptom described above.

12. Quick-Reference Fault Code Map

13. Frequently Asked Questions