VM replication cannot login to target site

[jump_tsang]

my site have a vcenter 5.5.0, 1750787, with vsphere replication appliance 5.8.1

and recently , I setup a new vcenter 6.0.0, 5318200 with replication appliance 6.1.2

I tried to replicate vm from vcenter 6.0 to 5.5 , it ask for Platform Services Controller login for target site instead of vcenter login id.

I cannot login to my target  vcenter 5.5 , is there compatible issue occur ?

Thanks

[admin]

That configuration will not work - vCenter and Replication major version must be the same at each site.