Can't connecto to target_ESX_IP:2500 after vCenter upgrade

[cmcc82]

After vCenter Server 4 upgraded to 5, and then Veeam 5 upgraded to 6 with Patch 3, Replication Jobs don't work.
There is a long error message, that says that the connected host (target ESX) at port 2500 can't connect.
We already check at firewalls, communication, networking and there are not problems. ESX still were version 4.1
Now we upgraded to ESXi 5 and still having that error. We deleted old jobs, re-created and still the same error.

Have someone had this error? Please help!

[Gostev]

There are quite a few existing discussions about this error, see if they help > http://forums.veeam.com/search.php?keyw ... ct+to+2500