Resolving SIMOTION SCOUT 4.1.2.4 Hotfix Installation Error

1. Problem Description

When attempting to install the SIMOTION SCOUT Hotfix 4.1.2.4 on a Windows engineering station, the setup halts with the error message:

This Hotfix SCOUT Needs 4.1.2.0

The installer refuses to proceed and rolls back, leaving the engineering environment in a non-functional state. The error is independent of the connected target hardware (D425, D425-2, D435, D445-1, D445-2, or D455) because the failure occurs before any device communication is initiated. The symptom is purely a Windows Installer dependency check failure between the base SCOUT package and the hotfix cumulative update.

This article documents the precise root cause, the supported recovery procedure, and the hardware/firmware context required to validate a clean install of the SIMOTION SCOUT V4.1.2 toolchain on a SIMOTION D4x5 control unit.

2. Affected Software and Versions

3. Root Cause Analysis

The error is produced by the Windows Installer (MSI) launch condition embedded inside the Hotfix 4.1.2.4 package. The launch condition evaluates a property such as SIMOTION_SCOUT_FOUND_VERSION against the registry key:

HKEY_LOCAL_MACHINE\SOFTWARE\Siemens\Automation\SIMOTION\Scout\4.1\Install

Specifically, the MSI verifies that the VersionMinor and VersionRevision values are at least 2.0. When SCOUT 4.1.2.0 has never been installed — only the hotfix executable was downloaded and launched — the registry branch does not exist, the launch condition fails, and the package emits This Hotfix SCOUT Needs 4.1.2.0 before any files are written.

Three common paths lead to this state:

1. Hotfix downloaded in isolation. A user pulls Hotfix 4.1.2.4 directly from the Siemens support entry SIMOTION SCOUT V4.1 SP2 HF4 without the prerequisite base media.
2. Base SCOUT installed under a different Windows account. The MSI looks up the install under the current user's context; if SCOUT was installed by another administrator, the registry hive is present but inaccessible to the current installer context.
3. Multiple SCOUT versions in parallel. SCOUT 4.1.2.0, 4.1.3, 4.2, and 4.4 use distinct install trees. The hotfix 4.1.2.4 will not attach to a SCOUT 4.1.3 or 4.2 base even if both are installed.

4. Solution: Install SCOUT 4.1.2.0 First

4.1 Obtain the SCOUT 4.1.2.0 Base Package

SIMOTION SCOUT is delivered on DVD and is shipped only against an active license (Express or Standard). The base package is not redistributed for free download. Procurement options:

• New license — order 6AU1800-1AA32-0XB0 (SCOUT 4.1 Standalone, single license) or the equivalent floating-license model.
• Software Update Service (SUS) contract — customers with an active SUS contract can request the latest SCOUT DVD through the Siemens SUS portal at no additional charge.
• Existing DVD — if the engineering team has the SCOUT 4.1 DVD (delivered between 2009 and 2010), use the discs as the bootstrap medium.

4.2 Install SCOUT 4.1.2.0

1. Insert the SCOUT 4.1 DVD or mount the ISO. If the autorun does not start, run setup.exe from the root.
2. Select the language (English, German, French, Italian, Spanish, Chinese — at minimum).
3. Accept the license agreement. The license terms cover SIMOTION SCOUT and the dependent SIMATIC S7 Technology optional packages.
4. Choose Complete installation to ensure the SIMOTION D / P / T configuration editors, the CamTool, the trace viewer, and the option packages are all present.
5. Enter the license key via Automation License Manager when prompted. If the dongle is not present, defer license transfer and use the 14-day trial mode for verification.
6. Complete the install and reboot. The setup writes the registry key HKLM\SOFTWARE\Siemens\Automation\SIMOTION\Scout\4.1\Install with Version = 4.1.2.0.

4.3 Install Hotfix 4.1.2.4

1. Download the hotfix ZIP from Siemens Support entry 34058968.
2. Extract the archive to a local folder; do not run from a network share that may be locked.
3. Close all SIMOTION SCOUT, SIMATIC Manager, and STEP 7 instances.
4. Right-click the hotfix executable and choose Run as administrator. The launch condition now finds 4.1.2.0 in the registry and proceeds.
5. Allow the install to overwrite the SCOUT 4.1 binaries in %ProgramFiles%\Siemens\Automation\SIMOTION\Scout\4.1.
6. Reboot the engineering station.

5. Verification Steps

1. Registry check. Open regedit and confirm VersionRevision = 4 under the SCOUT 4.1 install key. If only 2 is shown, the hotfix did not apply.
2. Help > About. Launch SCOUT. In the menu bar choose Help > About. The splash screen must report SCOUT V4.1.2.4 and the corresponding build number (e.g. 04.01.02.04_build005).
3. Project compatibility test. Open a known-good SIMOTION D project. The version stamp on the project file (.sim archive) must remain compatible. SCOUT 4.1.2.4 reads projects from 4.1.0 through 4.1.5 without upconvert.
4. Target online test. Connect the engineering station to a D425-2 (or any D4x5) via PROFINET or PROFIBUS. Run Online > Accessible Nodes. The D4x5 must appear with its SIMOTION kernel firmware version matching the SCOUT build.
5. Download & RUN test. Download the project to the D4x5. The drive must reach RUN state within 30 seconds. A failure to start RUN usually indicates a kernel/SCOUT version mismatch (e.g. SCOUT 4.1.2.4 paired with a SIMOTION V4.2 kernel on the D4x5).

6. SIMOTION D425-2 Hardware Overview

The SIMOTION D425-2 DP/PN (MLFB 6AU1425-2AD00-0AA0) is the second-generation D425 module with both PROFIBUS and PROFINET on-board. Key interface and I/O figures for this article's reference target:

For the broader SIMOTION D family, the 2011 product flyer (PDF) compares the D425, D425-2, D435, D435-2, D445-1, D445-2, and D455 controllers and is available at Flyer_SIMOTION_D_2011_Sep_en.pdf. The BASIC performance class of the D425-2 is positioned for medium-axis-count packaging machinery, multi-axis positioning, and synchronized cam applications where the larger D445-2 or D455 compute performance is not required.

7. SCOUT Software Architecture and Hotfix Mechanism

SIMOTION SCOUT is a Windows Installer-based engineering suite that depends on the SIMOTION Kernel Firmware on the controller and on several SIMATIC option packages (SIMATIC S7 Technology, SIMATIC S7-PCT, CamTool). The hotfix mechanism is intentionally narrow:

• Scope: A hotfix only patches SCOUT, the SIMOTION technology packages, the trace tool, the project converter, and the online diagnostics. It does not update the SIMOTION kernel on the D4x5 — that is done by downloading a new project that contains the desired kernel image.
• Roll-forward only. Hotfix 4.1.2.4 is cumulative on top of 4.1.2.0. You cannot downgrade with it; rolling back requires uninstalling hotfix 4.1.2.4 via Programs and Features and re-applying the 4.1.2.0 base files.
• Side-by-side versions. SCOUT 4.1.2.4, SCOUT 4.2, and SCOUT 4.4 can coexist in different install trees if multiple SIMOTION generations must be supported. The hotfix, however, only touches the 4.1 tree.

8. Licensing and Procurement Details

The SCOUT license model is enforced by Automation License Manager (ALM). Two common deployment patterns:

1. Local license on a USB parallel dongle. The dongle holds a license for SCOUT + a specific number of technology objects. The dongle must be plugged in on every engineering PC that runs SCOUT 4.1.2.4.
2. Network license via ALM server. A central server runs ALM and serves floating licenses. Each engineering PC must reference the server. The hotfix install is independent of the ALM topology; it is only the runtime that consults the license server.

Customers running a Software Update Service contract receive major and minor updates for the contracted period. Hotfixes are typically available for free download independent of the SUS contract. The 4.1.2.0 base is, however, contractually delivered; the SUS DVD image bundles every SCOUT release issued up to the DVD's manufacturing date.

9. Common Installation Errors and Diagnostic Matrix

10. Compatibility Matrix: SCOUT 4.1.2.4 vs SIMOTION D Controllers

11. Field Commissioning Checklist

1. Verify SCOUT 4.1.2.4 in Help > About before connecting to any hardware.
2. Confirm the D425-2 boot project specifies a SIMOTION V4.1.2 kernel image. If the project was authored in SCOUT V4.2, downgrade the project by Project > Change Version > To V4.1.2 before downloading.
3. Connect the engineering PC to the D425-2 service Ethernet port (X127 or similar) — not to the PROFINET ports. Set the PC IP to 192.168.0.x / 255.255.255.0 in the same subnet as the controller.
4. Run Online > Accessible Nodes. The D425-2 should appear with its IP and PROFINET device name.
5. Download the project. The D425-2 transitions through STOP > STARTUP > RUN within 30 s.
6. Open the trace viewer and record a test motion to confirm SCOUT-to-drive communication through DRIVE-CLiQ is healthy.