I'm preparing to upgrade from 2007 to 2010, and I've been reading Technet articles, Exchange team blog posts, and the Deployment Assistant, and I have some questions that I can't seem to find answers to. 1. Legacy domain name - Microsoft "recommends" using legacy.domain.com for the legacy CAS server in the Deployment Assistant. In this doc: http://technet.microsoft.com/en-us/library/dd351133.aspx It says that it "should be" legacy.domain.com. However, neither explains how Ex2010 knows what domain name you're actually using. How does it know where to pass legacy traffic? 2. SAN Cert - So I'm going to need a new san cert with what I'm using now on 2007, mail.domain.com, plus autodiscover.domain.com, plus legacy.domain.com (per recommendation or requirement, depending on which doc you're reading), and maybe outlook.domain.com if I am setting up a CAS array. I'm supposed to install that on the 2010 CAS box, export it and install it on the 2007 CAS box. The question here is that on my existing CAS, I was advised when setting it up (don't have the doc URL handy any longer, sorry) that I needed to include the NetBIOS name of the CAS server, plus the FQDN of the AD domain, such as cas2k7.domain.internal on the SAN cert for the CAS. Is this no longer needed for 2010? Also, in the Deployment Assistant, all it says is to use this command: Import-ExchangeCertificate -Path c:\certificates\import.pfx -Password:(Get-Credential).password to import the cert and do nothing else. Do you need to Enable-ExchangeCertificate for anything? It doesn't seem like just having the cert sitting there is going to do any good without actually using it. Those are the things that are jumping out at me initially, any guidance on those issues would be much appreciated.

No, completely unclear, what Exchange 2007 URLs do you change? And where is this done? Also, the list of URLs you list don't match what's in the Deplyment Assistant. In the section about adding digital certificates it specifically lists the domains needed: mail.domain.com autodiscover.domain.com legacy.domain.com domain.com It never mentions putting netbios names or FQDN internal names (which is what I meant by the FQDN of the AD domain, sorry that wasn't clear), so how am I supposed to know those are still needed?

That is exactly the info I needed, thanks. I've been working with Exchange since 5.5 and upgrade documentation is usually excellent, but Microsoft's instructions to get to 2010 are terrible. If you followed the instructions in the Deployment Assistant exactly as they're given, you'd blow up your environment.