The second message is only a warning to not install vshield app in the same host where vshield manager or virtual center reside.
Is the vShied App getting installed ?, if not ,check clock in ESXi, vCenter and and vShield manager, all must have the same config.
I´ve checked the time - there are no differences.
When I install the appliance anyway I get the first error message again and additionally the advise:
Following VMs from previous, bad or unknown
installations need to be removed manually:
<hostname of the appliance which couldn´t be created>
Try to remove it manually:
#esxcli software vib list | grep -i vshield
#esxcli software vib remove -n <package name>
Delete the vShield-FW-<IP> virtual machine from vCenter Server Inventory.
On the ESX host, navigate to Configuration > Software and click Advanced Settings.
Remove the IP address from /Net/Net.DVFilterBindIpAddress.
Also remove vSwitch if was created a try reinstalling again.