Just ensure that the
1-VMware VirtualCenter Management Webservices and
2-VMware VirtualCenter Server
services are both 'Started' and you are good to go.
For Windows 7 or Vista
Select the bottom-left Windows Orb, and in the search box, type Services. Under the heading "Control Panel", select View local services.
For Windows XP:
Click on Start, Control Panel, and Administrative Tools. In the pane, select Services.
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