Fix COMADMIN_E_START_APP_DISABLED (0X80110451)

Quick Answer (for advanced users)

Open Component Services, find the disabled COM+ application, right-click, go to Properties -> Advanced -> uncheck "Disable this application", then restart the COM+ System Application service.

What's Actually Happening

Error COMADMIN_E_START_APP_DISABLED (0X80110451) means the COM+ application itself is flagged as disabled in its configuration. This isn't a crash or a permission failure — it's a deliberate setting that got toggled, often by Group Policy, a third-party security tool, or someone fumbling around in Component Services. You'll see this most often on Windows Server (2008 R2 through 2022) when a legacy internal line-of-business app suddenly stops working after a patch Tuesday reboot. The event log usually shows Event ID 4199 from source COM+ with the same error text. The fix is straightforward, but you need to know where to look.

Fix Steps (Numbered Order)

1. Open Component Services — Press Win+R, type dcomcnfg, hit Enter. This opens the console under Administrative Tools.
2. Navigate to the app — Expand Component Services -> Computers -> My Computer -> COM+ Applications. Find the app throwing the error. It's usually named something like "MyApp" or a GUID.
3. Check the disabled flag — Right-click the app, select Properties. Go to the Advanced tab. Look for the checkbox labeled "Disable this application". If it's checked, that's your culprit.
4. Uncheck it — Uncheck the box, click OK.
5. Restart the COM+ System Application — Open Services (services.msc), find "COM+ System Application", right-click, Restart. This clears any cached disabled state.
6. Restart the app — Back in Component Services, right-click your app again and choose Start. It should start without the error now.

Alternative Fixes When the Above Fails

If the checkbox is already unchecked and it still won't start, try these:

• Check Group Policy — Run rsop.msc, look under Computer Configuration -> Administrative Templates -> Windows Components -> Application Compatibility. A policy named "Disable COM+ applications" exists and overrides local settings. Disable that policy or remove the app from its blacklist.
• Reset the COM+ catalog — Stop the COM+ System Application service. Delete the COM+ registration database (file path: %SystemRoot%\registration\*.clb). Restart the service. This rebuilds the catalog from scratch. Back up any custom COM+ apps first.
• Re-register the COM+ app — If the app came from an installer, run its setup again in repair mode. This re-registers the components and resets the disabled flag.
• Check for corrupted identity — Go to the app's Properties -> Identity tab. The account running the app might be locked or disabled. Switch to "Interactive User" temporarily to test. If it works, put it back on a valid service account.

Prevention Tips

• Document any manual changes in Component Services. This flag doesn't flip itself — someone or something changed it.
• Audit Group Policy regularly. I've seen well-meaning security baselines disable COM+ apps thinking they're attack surface.
• Set a monitoring alert for Event ID 4199 on your COM+ application server. Catch it early before users report it.
• If you're deploying a new COM+ app, test it on a clean server first. Some installers set the disabled flag as a safety measure — you have to enable it manually.

That's it. You're not dealing with a corrupt DLL or a permissions nightmare — it's a single checkbox. Don't waste time reinstalling or rebuilding the server. Just uncheck the box and get back to work.