What the available evidence confirms
The installation exposes more than one detection signal, but the evidence does not identify a single documented official test. An installer component ID exists in the registry, and the installed files reside under the OPC Foundation directory. The component ID value and its registry location are not provided, so do not guess either one.
| Detection method | Supported use | Limitation |
|---|---|---|
| Installed-programs list | Manual confirmation that the Core Components installer is listed | Not the strongest unattended-install check |
| Installer component ID | Installer-driven detection through registry-backed component information | The evidence does not supply the ID or registry path |
| OPC Foundation directory | Confirm that the directory exists and contains DLLs | File presence alone does not prove installer registration |
Detect the components during installation
- Obtain the installer component ID from the supplied merge module. An installer authoring tool can use that ID for detection; Orca.exe can extract the required merge-module information.
- Configure the installer to query that component rather than using an assumed registry location. The available evidence confirms a registry-backed component ID but does not identify its key or value.
- As a secondary check, resolve
%CommonProgramFiles%and%CommonProgramFiles(x86)%, then inspect the applicableOPC Foundationdirectory for DLLs. - For manual verification, open Control Panel, select Uninstall Programs, and check for the Core Components installer.
Avoid hard-coded installation paths
The Core Components destination cannot be changed during installation, but code should still resolve the common-files environment variables instead of hard-coding C:\Program Files (x86)\Common Files\OPC Foundation. Check the paths derived from both %CommonProgramFiles% and %CommonProgramFiles(x86)%; the evidence does not establish that one literal path is valid for every target system.
FAQ
How do I detect OPC DA Core Components in an installer?
Use the installer component ID contained in the merge module. Extract it with Orca.exe and configure the installer package to detect that component.
Where are OPC DA Core Components installed?
Resolve %CommonProgramFiles% and %CommonProgramFiles(x86)%, then check the corresponding OPC Foundation directory. Do not assume the literal C:\Program Files (x86)\Common Files\OPC Foundation path on every system.
Does finding OPC Foundation DLLs prove the components are installed?
It confirms that relevant files are present, but it does not establish installer registration by itself. Use component-ID detection for the installation decision and the directory check as supporting verification.
