Ashokvsetty,
Can you please create a new thread for any new issue. This is much like our support process, and also makes sure to keep a thread pure to one issue.
The error would be about trying to create a new System vDC resource pool, potentially in another cluster. When a shadow is created it goes into the System vCD, so it doesn't count against any specific Org vDC.
when you start a new thread, take a look at your vCenter Hosts/cluster view. if one System vDC already exists, see if there are any VMs inside of it. screen captures will be helpful.