Hi! Our internal our CAS 2007 servers today are set to the same as the external namepace, webmail.company.xx. Our clients are only allowed to use webmail internal so the external url is not really in use for our OWA users. When we will install our first cas server, should we change the internal url on the 2007 servers to serverfQDN since the fqdn of webmail.company.xx will be pointing to our 2010 servers behind our loadbalancer? UC

You will need to change the internal URL to something, so the internal FQDN would be expected. Exchange 2010 doesn't proxy to the old versions, it redirects. Therefore after logging in to Exchange 2010 (via the load balancer) they will need to be directed to the Exchange 2007 platform. Simon. Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.

Hi again! I forgot to ask about the internalUrl for EWS, in exchange 2007 the internalUrl is the same as the Owa url. When we change the webmail to point to exchange 2010, this would also include the EWS. Will there be a problem for us or should we change the internalUrl for the e2007 servers EWS to a new Url and if so, how would this affect our clients? Thanks!

Be consistent. Anything else will be a mess. So if you are changing the internal URL on OWA, change the others to the same host name as well. Simon. Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.