Fix COMADMIN_E_AMBIGUOUS_APPLICATION_NAME (0x8011045C)

Duplicate Application Name in COM+ Catalog

This error pops up when you try to register or configure a COM+ application and there's already two or more entries with the exact same name in the COM+ catalog. The system can't figure out which one you mean. Happens all the time after a botched uninstall or when someone manually copies applications between servers.

Here's the fix.

1. Open Component Services: hit Win + R, type dcomcnfg, press Enter.
2. Expand Component Services → Computers → My Computer → COM+ Applications.
3. Look through the list. You'll see two (or more) entries with the same name. Right-click the one you don't want (usually the older one or the one with a weird GUID in the description) and choose Delete.
4. If the delete fails, you'll need to stop the COM+ System Application service first. Run net stop "COM+ System Application" as admin, then delete the entry, then restart the service with net start "COM+ System Application".
5. Rebuild your app using whatever installer or script you were using. Should go through clean now.

Pro tip: If you're paranoid, export the COM+ catalog before deleting anything. Use the Component Services snap-in, right-click My Computer → Export. Saves you if you delete the wrong one.

Stale Registry Entries from an Uninstall

Sometimes the COM+ catalog looks clean, but the registry still has orphaned references. This usually happens when someone uninstalled an application without using its proper installer — they just deleted files or ran an old regsvr32 -u that didn't clean up properly.

Check these registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\COM3\Applications
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\AppID

Look for entries matching your application name or GUID. If you see duplicates, delete the stale ones. Backup the key first — right-click → Export. I've seen admins accidentally nuke the entire COM+ registration this way.

After cleaning the registry, restart the COM+ System Application service and try again.

Corrupted COM+ Catalog After Crash or Power Loss

If the above steps don't fix it, the catalog itself might be hosed. Happens after a server crash or forced reboot while COM+ was mid-write. You'll see weird behavior — apps show up in the list but can't be deleted or modified.

Your options here:

• Restore from backup. If you have a recent COM+ export file (.msi or .reg), import it via regsvr32 /i or Component Services Import.
• Rebuild the application from scratch. Delete all duplicate entries manually (as in Cause #1), then re-register your DLLs with regsvr32 and set up the COM+ application again.
• As a last resort, you can delete the entire COM+ Applications node and rebuild it. This is nuclear. Only do this if you have a backup of all your COM+ apps. To force delete stuck entries, use the command line:

cd /d %windir%\system32
 comadmin.exe /delete "YourAppName"

If comadmin.exe won't work, you can try deleting the catalog files directly (stop COM+ System Application service first, then delete everything under %windir%\registration, then restart the service). I've done this maybe three times in 14 years — only when nothing else worked.

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