Your experiences with 2007/2003 interoperability

blargoe

I am working updating the networks of our sister office in China into a single network and a child domain in our Active Directory. I have had a plan put together for months that involved a new Exchange 2003 server to replace their existing one and doing a simple mailbox move. Then remove the old server. Simple. Actually, there's a lot more going on, but that was all for Exchange.

I had the bomb dropped on my last week that it has been decided for me that Exchange 2007 will be implemented there instead. I'm a little ticked about it this late in the game, but actually kind of excited that I will get to go ahead and work with it soon.

I was really just wondering if any of you have had an org with 2007 and 2003 servers running for any length of time and what your experiences have been. We're going to have to have interoperability for a year or so before I will be able to upgrade our Corporate office. The final result when I am done in China will be having a their site completely 2007, and our corporate office completely 2003, with routing between the sites over our WAN link as it occurs today.

HeroPsycho

The co-existence environments I've seen have been mostly fine, aside from a few things here and there.

The biggest issue I've seen, and this isn't really focused on a co-existence scenario, are problems associated with CAS servers across remote sites not able to connect to each other. Causes all kinds of funny business, such as not being able to see free/busy information, not able to create profiles with O2K7 clients using the availability service, that kind of thing.

royal

That's because the majority of people don't understand how to set up CAS-CAS proxying/re-direction. Need to do quite a bit of manual work such as configuring the AutodiscoverInternalURI, Integrated Authentication on the CAS servers in intranet sites, leave ExternalURL at $null in remote intranet sites, and have both ExternalURL and InternalURL configured correctly on the CAS that clients will be connected to from the Internet. There's also optimization that can be done such as Site Affinity.

Seems like a lot of people just don't understand how to get CAS servers working in a multi-site topology.

HeroPsycho

It's also that people assume that E2K7 works as E2K3 did in respect to free/busy, when it doesn't. I've been brought in to businesses with customers who still have demand dial links between the sites and can't understand why they can't see when someone is available at another site. It is not a replicated folder anymore if you're using Outlook 2007 clients.

You can make the argument this is actually a technical weakness of Exchange 2007, but it's one of those things people assumed it worked as it did in the last release when it clearly doesn't.