When the VMware Operations Manager appliance is corrupted or deleted, the vCenter Operations Manager plugin remains in the vCenter Server showing an error.
To keep the system clean is necessary to remove the extension from the Plug-in Manager.
Procedure
First step is removing the asset stored in vCenter Server. From vSphere Client, log on to system and go to Home > Licensing. Right click the vCenter Operations Manager item and select Remove Asset option.
Click Yes to confirm removal.
From your browser, enter the vCenter Server https address and log on the system with an administrative account using the URL:
https://vcenter_address/mob
From ServiceContent type, click content value.
Click ExtensionManager.
Click UnregisterExtension.
To remove the Operations Manager plugin, enter in the extensionKey field the string:
com.vmware.vcops
Then click Invoke Method.
When the removal completes, you receive void as notification result.
Restart vSphere Client and open the vCenter Server Plug-in Manager. The Operations Manager plugin should have been removed.
This procedure is good to remove other extensions as well. Just type the correct extensionKey value then click Invoke Method.