In some rare occasion, you may end up with an orphaned VM in your vCenter inventory where no “remove” option is available from the option menu.
Beside doing the removal using the CLI, there is still a way that worked most of the time for me.
1. Browse to “VMs and Templates inventory” inside the vCenter client/WebUI
2. Create a new (temporary folder) with any name of your choice
3. Drag and drop the orphaned VM into that new folder you just created
4. The “remove” option should now be available for that orphaned VM, just delete it as you would do normally and delete that temporary folder.