Best Practices for Deploying ActiveX Compatibility Manager in Enterprises

How to Use ActiveX Compatibility Manager to Fix Browser Plugin IssuesActiveX controls were once a common way to add interactive functionality to web pages — video players, document viewers, custom UI widgets and more. Over time, browsers and web standards have moved away from ActiveX because of security and compatibility concerns. When legacy web applications still rely on ActiveX, organizations can use the ActiveX Compatibility Manager (ACM) to reduce compatibility problems while keeping services running. This article explains what ACM does, when to use it, step-by-step instructions for using it, troubleshooting tips, and best practices for migrating away from ActiveX.

What is ActiveX Compatibility Manager?

ActiveX Compatibility Manager (ACM) is a tool designed to help manage, mitigate, and troubleshoot compatibility issues related to ActiveX controls in environments where older web applications or intranet sites still rely on them. ACM can identify problematic controls, apply compatibility settings, and coordinate with browser policies to allow legacy controls to run safely or be restricted where necessary.

Key functions typically include:

• Detecting installed ActiveX controls and their versions
• Applying compatibility settings or shims for specific controls or sites
• Logging and reporting compatibility problems
• Integrating with group policy or enterprise deployment tools

When to use ACM

Use ACM when:

• Your intranet or legacy web applications require ActiveX controls that modern browsers block or treat inconsistently.
• You need to selectively enable specific ActiveX controls for particular sites without broadly weakening browser security.
• You are preparing to migrate away from ActiveX but need an interim solution to keep services functional.
• You want centralized control over which controls run and under what conditions (e.g., only on certain servers or for certain users).

Preparatory steps

1. Inventory and assess:

   • Identify which web applications use ActiveX and which specific controls those apps require.
   • Make a list of controls (CLSID, file names, vendor, version) and the sites that host them.

2. Backup configurations:

   • Export current browser and system policies before changing settings.
   • Ensure you have system backups or snapshots for testing rollback.

3. Gather tools:

   • Obtain the latest version of ActiveX Compatibility Manager (or the specific enterprise tool you use).
   • Ensure administrative access to the machines or management consoles where you’ll apply settings.

4. Establish test environment:

   • Set up a staging environment that mirrors production to validate changes safely.

Step-by-step: Using ActiveX Compatibility Manager

Note: Exact UI elements and commands may differ by vendor/version. The following is a general workflow.

1. Install and open ACM

   • Install the ACM tool on a management workstation or server.
   • Launch the console with administrative privileges.

2. Scan systems and browsers

   • Run a discovery scan to detect installed ActiveX controls on target machines or image files.
   • Scan web pages or a list of URLs to identify which ActiveX controls they attempt to load.

3. Review detected controls

   • Examine the detected controls’ metadata: CLSID, filename, publisher, version, and digital signature status.
   • Prioritize controls by criticality and known security risk.

4. Create compatibility entries (shims/policies)

   • For each control that needs to be allowed, create a compatibility entry. Typical settings include:
     • Allowed/blocked status
     • Whitelisted hostnames or URLs where the control may load
     • Required security zones (e.g., Intranet only)
     • Version constraints (minimum/maximum versions)
     • Execution contexts (e.g., only for signed controls)
   • For controls known to be problematic, create mitigations (disable certain features, force UA string, emulate legacy browser behavior).

5. Deploy settings

   • Publish the compatibility settings to target machines via Group Policy, SCCM, Intune, or the ACM’s deployment mechanism.
   • Apply settings first to the staging group, monitor effects, then roll out to production.

6. Test functionality and security

   • On test machines, load the relevant web pages and verify controls behave as expected.
   • Check security logs and browser consoles for errors or blocked content.
   • Verify that other sites are not inadvertently affected.

7. Monitor and adjust

   • Use ACM’s reporting to track which controls load and which were blocked.
   • Update rules when controls are upgraded or when new sites require access.
   • Remove allowances when legacy functionality is retired.

Troubleshooting common issues

• Control still blocked after creating an allow rule:

  • Confirm rule target matches the exact hostname and protocol (http vs https).
  • Verify the control’s CLSID and file signatures match the entries in ACM.
  • Ensure policy propagation completed (gpupdate /force) and browser caches were cleared.

• Broken functionality after allowing a control:

  • Check whether the control’s version is incompatible with browser process architecture (32-bit vs 64-bit).
  • Look for missing dependencies (DLLs, runtimes) on client machines.
  • Test running the control in a clean profile or VM to isolate environmental issues.

• Security warnings or prompts persist:

  • Ensure controls are properly signed with a valid certificate and that the certificate chain is trusted.
  • Consider adding trusted publisher entries only for signer certificates rather than broad allow rules.

• Performance or stability problems:

  • Identify whether a specific ActiveX control causes browser crashes; use crash logs and Windows Event Viewer.
  • Limit the control’s scope (only specific pages/users) while investigating alternatives.

Migrating away from ActiveX — plan while using ACM

ACM is a bridge, not a long-term solution. Create a migration plan:

1. Prioritize web apps for modernization:

   • Triage by business value, usage frequency, and technical feasibility.

2. Choose modern alternatives:

   • Replace ActiveX with standards-based technologies: HTML5, WebAssembly, JavaScript libraries, PDF/Office web viewers, or native applications with secure APIs.

3. Develop and test replacements:

   • Build modern equivalents in parallel, test in staging, and validate feature parity and security.

4. Phased roll-out:

   • Deploy replacements to subsets of users, monitor, and collect feedback.
   • Gradually disable ActiveX compatibility entries for retired apps.

5. Decommission:

   • Remove ACM allowances and related legacy policies once migration completes.

Best practices and security considerations

• Principle of least privilege: allow only the specific controls and hosts necessary.
• Use site-restrictions: prefer whitelisting hostnames rather than broad Allow for all sites.
• Prefer signed controls: require digital signatures and trust only known publishers.
• Monitor logs: regularly review which controls are allowed and how often they’re used.
• Keep inventories current: record control versions and retire entries for unused controls.
• Communicate with stakeholders: inform users of planned changes and expected timelines.
• Plan for incident response: have rollback procedures and quick ways to revoke allowances if misuse is detected.

Example ACM rule set (conceptual)

• Allow: CLSID {XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX} — Host: intranet.corp.local — Condition: Signed by Contoso Ltd — Zone: Local Intranet — Versions: >= 2.0
• Block: CLSID {YYYYYYYY-YYYY-YYYY-YYYY-YYYYYYYYYYYY} — Condition: Unsigned or Outdated
• Shim: Emulate legacy user-agent for example-legacy-app.corp.local to resolve scripting differences

Conclusion

ActiveX Compatibility Manager helps organizations continue running legacy ActiveX-dependent applications while controlling security risk and easing the migration to modern web technologies. Use ACM to identify controls, create narrowly scoped compatibility rules, test carefully, and pair the use of ACM with a clear modernization plan. Over time, replace ActiveX functionality with standard, secure web technologies to eliminate the need for compatibility shims.