problem to add vcenter 5.5 and 6.5 to opmanager

problem to add vcenter 5.5 and 6.5 to opmanager

hello
i want to add vcenter 5.5 and 6.5 to opmanager 12.5.129 but dont add and a error occurd
:Failed to connect the VMware Host WebService(Device may not be reachable/Credentials may be wrong)

Thanks

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