It would have been helpful if you had combined these posts
First, I would check hostname resolution in both directions. From the command prompt on the Installation Server:
nslookup [client hostname] Do not include the [ ] marks
and from the command prompt on the client
nslookup [cell manager hostname]
I found one lab case on this issue, that reported the problem was with the INET process, and was ultimately caused by the incorrect installation of a patch bundle