I must install Zcm 11 on a customer on windows 2008 R2 and i receive warning on DNS during installation.

My server has static IP
DNS server is configured with register A and PTR
i can ping -a @IP = static IP-->myserver.zone.loc
I can ping myserver.zone.loc

But i don't understand why installation sends me again this warning??

If you have an idea.

Thx a lot