Resolving TIA Portal V16 Library Compare UmacDelegate Error

Problem Overview

The Siemens application example "TIA Openness Library Compare" (entry ID 109749141) is a C# utility that automates the comparison of project libraries and global libraries between two TIA Portal projects. The published binary targets TIA Portal V13/V14 and binds to Siemens.Engineering.dll at version 14.0.1.0. When you run the tool against TIA Portal V16 or V17 installations, it throws a reflection loading exception and never reaches the compare engine.

The error appears immediately after the project selection dialog closes, before the compare progress bar renders. The tool cannot continue without a code rebuild that targets the new TIA Portal Openness API surface and registry layout.

Error Symptoms and Stack Trace

The full type-load failure returned to the GUI is:

Could not load type 'Siemens.Engineering.UmacDelegate' from assembly
'Siemens.Engineering, Version=14.0.1.0, Culture=neutral, PublicKeyToken=d29ec89bac048f84'

Secondary symptoms reported in the field:

• Similar failures for Siemens.Engineering.ProjectBase when the user attempts V15.1 with a V15.1-targeted build (Version=15.1.0.0 missing types).
• File enumeration in Openness.cs fails to recognize .ap16 and .ap17 archive extensions and silently skips project folders.
• Missing NuGet packages (Microsoft.Expression.Interactions) prevent the Release build from completing.

Root Cause Analysis

The application example ships with a static switch statement in Resolver.cs that maps a detected TIA Portal version to:

• Display version string (V13, V14, V15, V15.1).
• TIA Portal internal build number (13.00.0000, 14.00.0000, 15.00.0000, 15.01.0000).
• Global library subfolder.
• STEP 7 and Openness registry paths under SOFTWARE\Siemens\Automation\_InstalledSW\TIAPxx.

Entries for V16 and V17 are missing. Without a case branch for the installed TIA Portal, the resolver falls back to the V14 binding, and at runtime the Common Language Runtime attempts to materialize UmacDelegate from Siemens.Engineering 14.0.1.0, which does not contain the type signature expected by the V14-targeted IL. The assembly loader then throws the TypeLoadException shown above.

Two further compounding issues exist in the example source:

1. The LibraryCompare.Openness project references Siemens.Engineering 14.0.1.0 by NuGet fallback; it must be repointed to the Siemens.Engineering.dll shipped with TIA Portal V14 SP1 (or higher) and marked Copy Local = false so the GAC-shipping Openness assembly is loaded at runtime.
2. The file filter in Openness.cs uses an exact match on .ap14, which excludes V16 (.ap16) and V17 (.ap17) project archives.

Prerequisites

Confirm the following before modifying the source:

• Microsoft Visual Studio 2017 or 2019 with the .NET desktop development workload installed.
• .NET Framework 4.8 Developer Pack (required for the project assemblies).
• TIA Portal V16 with Openness installed (or V16 and V17 both present for multi-version compare).
• Siemens TIA Portal Openness V14 SP1 DLL set (the reference DLL family) extracted to a known folder, or the DLLs copied from C:\Program Files\Siemens\Automation\Portal V14 SP1\PublicAPI\V14 SP1.
• Local administrator rights so the rebuilt tool can read the SOFTWARE\Siemens\Automation\_InstalledSW\TIAPxx registry hive.
• NuGet access for Microsoft.Expression.Interactions (typically restored automatically by Visual Studio).

Step-by-Step Solution

1. Open the Source Solution

Extract the downloaded ZIP 109749141_TIA_OpennessLibraryCompare_PROJ_V13.zip to a working directory and open:

109749141_TIA_OpennessLibraryCompare_PROJ_V13\LibraryCompare-SourceCode\Open LibraryCompare.sln

Visual Studio will load three projects: LibraryCompare.GUI, LibraryCompare.Core, and LibraryCompare.Openness.

2. Update the Resolver Switch Statement

In the Solution Explorer, expand LibraryCompare.Core and open Resolver.cs. Locate switch in the Resolve method (line 123 in the published source). Insert two new case branches before the default block:

case "16.0":
    _versionString = "V16";
    _tiaVersionNumber = "16.00.0000";
    _subFolder = "V16";
    _step7Registry32Bit  = "SOFTWARE\\Siemens\\Automation\\_InstalledSW\\TIAP16\\STEP7";
    _step7Registry64Bit  = "SOFTWARE\\Wow6432Node\\Siemens\\Automation\\_InstalledSW\\TIAP16\\STEP7";
    _opennessRegistry32Bit = "SOFTWARE\\Siemens\\Automation\\_InstalledSW\\TIAP16\\TIA_Opns";
    _opennessRegistry64Bit = "SOFTWARE\\Wow6432Node\\Siemens\\Automation\\_InstalledSW\\TIAP16\\TIA_Opns";
    break;

case "17.0":
    _versionString = "V17";
    _tiaVersionNumber = "17.00.0000";
    _subFolder = "V17";
    _step7Registry32Bit  = "SOFTWARE\\Siemens\\Automation\\_InstalledSW\\TIAP17\\STEP7";
    _step7Registry64Bit  = "SOFTWARE\\Wow6432Node\\Siemens\\Automation\\_InstalledSW\\TIAP17\\STEP7";
    _opennessRegistry32Bit = "SOFTWARE\\Siemens\\Automation\\_InstalledSW\\TIAP17\\TIA_Opns";
    _opennessRegistry64Bit = "SOFTWARE\\Wow6432Node\\Siemens\\Automation\\_InstalledSW\\TIAP17\\TIA_Opns";
    break;

The registry layout matches what TIA Portal V16 and V17 installers write under HKLM. The 32-bit entries remain because legacy installers (and 32-bit Openness probes) still write them, while the 64-bit equivalent lives under the WOW6432Node reflection hive.

3. Repoint the Openness DLL Reference

Open the LibraryCompare.Openness project and remove the existing Siemens.Engineering assembly reference. Add a new reference, browse to the V14 SP1 PublicAPI folder, and select Siemens.Engineering.dll (version 14.1.0.0 or matching the V14 SP1 install). After adding the reference, set the following properties in the Visual Studio Properties window:

Open the build output folder (bin\Release) of LibraryCompare.Openness and delete any Siemens.Engineering.*.dll files copied in by an earlier build. The runtime must load the GAC-installed version of the assembly that ships with the active TIA Portal.

4. Target .NET Framework 4.8

For each of the three projects (LibraryCompare.GUI, LibraryCompare.Core, LibraryCompare.Openness):

1. Right-click the project and choose Properties.
2. Open the Application tab.
3. Set Target framework to .NET Framework 4.8.
4. Save the project file.

Visual Studio will prompt to retarget; accept and rebuild. .NET 4.8 is required because the rebuilt tool uses async I/O patterns and modern C# features not available in 4.5/4.6.

5. Patch the Archive Extension Filter

Open Openness.cs in LibraryCompare.Openness and navigate to line 232. The original guard is:

if (fileInfo.Extension == ".ap14")

Replace it with a contains check that matches all TIA Portal archive generations:

if (fileInfo.Extension.Contains(".ap1"))

This pattern matches .ap13, .ap14, .ap15, .ap16, and .ap17. If you need to restrict to a specific generation, replace with explicit Or clauses for each extension.

6. Restore NuGet Packages

If the build fails with a missing reference to Microsoft.Expression.Interactions, restore via:

Tools > NuGet Package Manager > Package Manager Console
PM> Update-Package -reinstall

or right-click the solution and choose Restore NuGet Packages. The Expression Interactions assembly is required by the WPF binding glue in LibraryCompare.GUI.

7. Build the Release Binary

From the Visual Studio menu:

1. Build > Clean Solution to remove stale intermediate output.
2. Set the solution configuration to Release in the toolbar dropdown.
3. Build > Build Solution (Ctrl+Shift+B).

The output binary lives at LibraryCompare.GUI\bin\Release\LibraryCompare.GUI.exe. Copy the entire Release folder to a deployment location and launch the executable as administrator.

Verification

Validate the rebuilt tool with the following checks:

1. Project load test: Open two TIA Portal V16 projects (or V16 vs V17) using the "Load Project" dialog. The browser must list .ap16 archives.
2. Compare execution: Click Start Comparison. The progress bar should reach 100% and the compare editor should display block-level diffs.
3. Registry probe: With the tool running, attach Process Monitor (ProcMon) and filter for RegOpenKey on TIAP16 or TIAP17. Successful keys should be queried, missing keys should produce a graceful "TIA Portal not installed" message rather than a crash.
4. Cross-version regression: Run the tool on a TIA Portal V15.1 project to confirm that the original V15.1 branch of the switch statement still functions.

Native TIA Portal Library Compare Alternative

If rebuilding the C# tool is not feasible, TIA Portal provides a built-in compare editor that does not require any Openness code. According to the Siemens FAQ 81748055 and the TIA Portal V20 documentation:

1. Enable the Reference projects view via View > Reference projects in the Project tree.
2. Open the first project as the active project.
3. Open the second project as a reference project.
4. Open the Libraries task card, right-click the project library or global library, and select Start comparison.
5. Use the compare editor to step through added, deleted, and modified library elements.

The built-in compare editor is available in TIA Portal V15.1 and later, and supports offline/offline project comparison as well as project-to-library and library-to-library comparison without any external tooling.

Troubleshooting Matrix

Field-Proven Caveats and Edge Cases

Several practical considerations apply when deploying the rebuilt tool on a production engineering workstation:

• Multi-version workstations: If a single machine hosts TIA Portal V15.1, V16, and V17, the tool will resolve to the highest version that matches the registry scan order. To force a specific version, close all higher-version TIA Portal instances and rename the corresponding registry hive temporarily.
• User administration differences: The UmacDelegate error is sometimes caused by mismatched UMAC (User Management and Access Control) configurations between the two projects being compared. Ensure both projects use the same user administration mode (local Windows users vs TIA project users).
• Project password protection: TIA Portal V16 project archives that are password-protected will not be loadable by the Openness API. Remove password protection before running the compare.
• Library version conflicts: The compare result highlights block-level differences but does not perform automatic merge. Use the TIA Portal compare editor to accept or reject individual changes.

FAQ