Step 7 SIMATIC Manager Cannot Open Projects Offline

Problem Description

When a service engineer or commissioning specialist disconnects a Windows 7 (or Windows 10/11) workstation from the office network, the SIMATIC Manager (part of the legacy STEP 7 V5.x toolchain) refuses to open any project, even when the project files are stored on the local hard disk. The SIMATIC Manager window stays empty after the user selects a project, clicks OK, and the status bar reads 0/0. Reconnecting the laptop to the LAN restores the open functionality within seconds. Once a project is opened while connected, it can subsequently be opened while disconnected — until the next reboot.

This symptom has been reproduced on STEP 7 V5.5 SP3 Hotfix 11 and STEP 7 V5.6 + SP1 (internal revision K5.6.0.1) running on Windows 7 Professional SP1 64-bit. The same pattern is reported on Windows 10 LTSC installations that have been upgraded from Windows 7 images without a clean SIMATIC Manager reinstall.

Affected Software and Versions

The S7-1200/S7-1500 toolchain (TIA Portal V13/V15/V16/V17/V18) is not affected by this class of fault. The issue is specific to the legacy STEP 7 V5.x installer family, which still ships a Windows NT 4.0–era service and shell extension layer.

Root Cause Analysis

STEP 7 V5.x is a 32-bit application (WOW6432 node) that has hard-wired dependencies on three Windows-side resources that all degrade or fail when the workstation is offline:

1. The S7ELEA and S7DOS services are installed as "manual start" in a default install. Their startup path uses the %ProgramFiles%\Siemens\Automation\Simatic Manager\s7elea.exe binary and registers itself as an event-log consumer. On machines where the Workstation service has not finished initializing because the network adapter is in a "no connection" state, S7ELEA enters a half-started state. SIMATIC Manager then refuses to enumerate offline projects because its COM object model relies on the event subscription.
2. The temporary file resolver for the project's .s7p and .s7f files uses a path that is computed at first open and cached in %LOCALAPPDATA%\Siemens\Automation\Temp. If the Setup wizard was launched the first time over a UNC path (e.g. \\fileserver\install\STEP7) the cached prefix can include a dead UNC reference. The repair function in Add/Remove Programs cannot rewrite this prefix because the installer requires the original MSI source, which the IT department may have already cleaned up — exactly the situation described in the field case ("Repair does not work because Temporary files are cleaned").
3. The s7hcomp.dll / s7eepa.dll COM server uses the Windows CryptoAPI certificate chain. Offline machines have no CRL reachable. The chain build fails after a default 5 s timeout. SIMATIC Manager treats the failed chain validation as a license failure and aborts the project open with no error dialog, which is why the user sees a silent 0/0 status.

After the first successful open while online, COM caches the valid certificate chain in %LOCALAPPDATA%\Microsoft\Crypto\RSA and the project can subsequently be opened offline until the cache is invalidated (e.g. reboot that clears PendingFileRenameOperations, or a Windows update that resets the CryptoAPI state).

Pre-Diagnostic Checklist

Before changing any registry, confirm the following:

1. The project really is on the local disk. Right-click the .s7p file in Explorer → Properties → verify the Location tab shows a C:\ or D:\ path, not a \\server\share\... UNC path.
2. Open Command Prompt → set TEMP and set TMP. Both must resolve to a local path. If either is mapped to a network share, fix this first.
3. Open Control Panel → Network and Sharing Center → Advanced sharing settings and confirm Turn on network discovery is enabled, even when offline, otherwise the offline file cache resolution layer reports "not found" to COM. Refer to the Microsoft article on shared folder access from File Explorer for the exact control path.
4. Verify the user has the Power User or Administrator group membership. Standard users on Windows 7 cannot write to the STEP 7 program data folder and the open silently fails.

Diagnostic Procedure

Run the following checks in order. Record the output of each before changing state.

1. Check service state: Run services.msc, locate S7ELEA and S7DOS. Both must be Running (or at minimum S7ELEA must be Started). Note the Log On As column — it should be Local System or a dedicated S7Service account, not the interactive user.
2. Check the binary: In %ProgramFiles%\Siemens\Automation\Simatic Manager\, confirm s7elea.exe, s7eepa.dll, and s7hcomp.dll all exist and have a non-zero size. A zero-byte file indicates a broken install.
3. Check the event log: Open eventvwr.msc → Windows Logs → Application. Filter for Source = S7ELEA and Source = S7DOS. Look for event ID 1001 entries with a description containing 0x80070002 (file not found) or 0x80004005 (unspecified error). These are the canonical fingerprints of the offline open failure.
4. Check the CryptoAPI cache: dir /s %LOCALAPPDATA%\Microsoft\Crypto. If the directory contains only stub folders, the certificate chain was never cached and every offline open will fail.
5. Check third-party software: Confirm presence of RSLogix 500/5000/Studio 5000. In the field case the customer is a service engineer with Studio 5000 Logix Designer, RSLinx, and RSNetWorx installed. Rockwell software registers its own ODBC data sources and a competing license manager (FlexNet Activation Service) that conflicts with S7ELEA on the same RPCSS endpoint. Disabling Rockwell software first will determine whether it is the trigger.

Step-by-Step Solution

The repair is structured in five layers. Apply them in the order shown; each layer is independent and the procedure can stop as soon as offline open succeeds.

Layer 1 — Re-prime the S7ELEA service

1. Open services.msc as Administrator.
2. Right-click S7ELEA → Properties → set Startup type to Automatic (Delayed Start).
3. Set Log On As to Local System account and tick Allow service to interact with desktop.
4. Click Start. If the start returns Error 1053: The service did not respond to the start or control request in a timely fashion, apply Layer 2 first.
5. Repeat for S7DOS and S7NTFLOG if present.

Layer 2 — Repair the missing temp cache

1. Close SIMATIC Manager.
2. Create the folder C:\ProgramData\Siemens\Automation\Temp (Windows 7 path) or %PUBLIC%\Siemens\Automation\Temp (Windows 10+).
3. Open Registry Editor as Administrator and navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Siemens\Automation\STEP7\V5.0\Application.
4. Confirm the value (Default) points to a local path. If it points to a UNC path (e.g. \\fileserver\install\...), replace it with C:\Program Files\Siemens\Automation\.
5. Reboot.

Layer 3 — Re-create the certificate cache

1. Connect to the network.
2. Launch SIMATIC Manager and open the project once.
3. Close SIMATIC Manager.
4. Copy the populated folder %LOCALAPPDATA%\Microsoft\Crypto\RSA to a USB stick for backup.
5. From this point on, the project will open offline until the next major Windows update that resets CryptoAPI.

Layer 4 — Eliminate the Rockwell conflict

1. Open appwiz.cpl and uninstall the Rockwell packages in this order: RSLogix 500/5000/Studio 5000, RSLinx Classic, RSNetWorx, FactoryTalk Activation Service.
2. Reboot.
3. Open SIMATIC Manager and open a local project while offline.
4. If successful, the workstation is dedicated to Siemens work only and Rockwell can be installed in a virtual machine (Hyper-V/VMware) for the rare cross-platform job.

Layer 5 — Clean reinstall (last resort)

1. Uninstall STEP 7 via appwiz.cpl.
2. Delete the folders C:\Program Files\Siemens\Automation, %ProgramData%\Siemens, and %LOCALAPPDATA%\Siemens.
3. Remove the registry keys under HKLM\SOFTWARE\Wow6432Node\Siemens and HKCU\SOFTWARE\Siemens.
4. Run msizap from the Windows SDK against any orphan MSI GUIDs: msizap.exe T {GUID}.
5. Reboot and install STEP 7 from a verified local copy of the install media, never a UNC path.

Windows-Side Remediation

Several Windows configuration choices silently break SIMATIC Manager offline. The following items must be set as shown before the offline open test will succeed.

SIMATIC Manager Configuration

Two settings inside SIMATIC Manager reduce the surface area of the offline failure.

1. Disable the project archive check: Options → Customize → Open/Save → uncheck "Check archive bit on open". This stops SIMATIC Manager from re-stamping the archive bit, which requires a writable share and silently fails offline.
2. Disable online partner lookup: Options → Set PG/PC Interface → select "S7ONLINE (STEP 7) -> TCP/IP" and on the Diagnostics tab uncheck Broadcast search. Broadcast does not work across VLANs and on a fully offline machine it stalls the partner enumeration for the full 30 s TCP timeout.

Third-Party Software Conflict (Field Case)

The original field report includes a very long list of co-installed software on a service laptop:

• TIA Portal V13 — compatible, no conflict
• Starter (SINAMICS commissioning) — compatible, but shares the S7DOS service on newer versions, do not run both at once
• SEW Motion Studio — does not interfere, uses its own OPC server
• ABB Robot Studio — does not interfere, uses a separate FlexNet port
• Cognex In-Sight / Keyence / Sick scanner software — does not interfere, but each installs a virtual network adapter that confuses the offline detection; disable the virtual adapters when travelling
• PROFINET IO Trace / IFM IO-Link container — does not interfere
• RSLogix 5000 / Studio 5000 / RSLinx — primary culprit; Rockwell's FactoryTalk Activation Service takes exclusive ownership of the same TCP port range (6000–6004) that S7ELEA uses for its license beacon

Confirmed in the field case: once the Rockwell stack was uninstalled, the projects opened offline without a VPN, on a fresh reboot, on the first try.

Verification

Validate the fix using this sequence. Each step must succeed before the next is attempted.

1. Disable the network adapter (do not just unplug the cable — that leaves the NIC in "acquiring" state).
2. Reboot.
3. Log in. Confirm ipconfig /all shows Media State = Media disconnected.
4. Launch SIMATIC Manager. Open a project from C:\Projects\<name>.s7p.
5. Confirm the status bar changes from 0/0 to 1/1 and the S7 program folder appears within 5 s.
6. Open Blocks, double-click OB1, confirm the editor opens in LAD/FBD/STL.
7. Edit a comment, save, close the block, close the project, close SIMATIC Manager.
8. Re-launch SIMATIC Manager and re-open the same project offline — the save state must be intact.
9. Re-enable the network adapter and confirm online open still works against a real S7-300/S7-400 CPU.

Long-Term Mitigation

For service engineers who travel frequently with a Siemens-only or mixed-vendor laptop, the following configuration prevents the offline open failure from re-occurring.

• Maintain a dedicated Siemens boot image on a separate partition, restored to a known baseline before each trip. STEP 7 V5.x is not designed for in-place upgrades and accumulates orphan registry keys that re-introduce the failure.
• Run Rockwell software inside a Hyper-V Gen 2 VM with a fixed virtual switch. The host keeps a clean S7ELEA environment; the VM provides isolated access to RSLinx/Studio 5000.
• Use a USB-Ethernet adapter as the primary Siemens network. The internal Wi-Fi can then be disabled before the offline test, eliminating the "media disconnected vs. media acquiring" ambiguity.
• Keep a snapshot of %LOCALAPPDATA%\Microsoft\Crypto\RSA after a successful online open, and a reg export of the HKLM\SOFTWARE\Wow6432Node\Siemens tree. Restore these in under two minutes if the CryptoAPI cache is ever wiped.
• For new projects on S7-1200/S7-1500, migrate to TIA Portal V18 or later which is offline-clean by design and is not affected by the legacy COM/CryptoAPI dependency chain.

Safety and Operational Notes

FAQ