During my failed installing of Exchange 2007, I've learnt that we have to enable IPv6 on Windows Server 2008 in order to install Exchange 2007 SP1. IPv6 isn't used in the LAN right now. I know that it's possible to remove the IPv6 within the registry, but I'd prefer keeping it for future usage when the time comes. But what IP address should I use? I suppose it's not a good idea to use "Obtain an IPv6 address automatically" since DNS and DHCP server services are installed in this WS2K8 computer. Currently, my LAN address is 10.1.1.0/24 (not /8). Should I use * unique local address, ie fc00::10.1.1.0/120 ? or * IPv4 transition, ie ::ffff:10.1.1.0/120 ? Visibly IPv4 transition address is easier to remember...

Registry method will just disable it and can be enable whenever you want by reverse changes so I would suggest you to disable it as per KB952842 and enable it when you implement IPv6 in your network. IPv6 for Microsoft Windows: Frequently Asked Questions http://technet.microsoft.com/en-us/network/cc987595.aspx IPv6 Support in Exchange 2007 SP1 http://technet.microsoft.com/en-us/library/bb629624.aspx Amit Tank | MVP - Exchange | MCITP:EMA MCSA:M | http://ExchangeShare.WordPress.com

You don't need to be using it on the LAN - you just need to have it enabled on the servers because it uses it for some internal communications.Carolhttp://www.wapshere.com/missmiis

Yes, the article IPv6 support in exchange 2007 SP1 from Amit has provided the consideration if you want to use IPv6, especially in the Exchange 2007 SP1 components that are directly affected by IPv6 table. You can decide whether to use IPv6 after see the article

Thanks for your answers. :) Even though I'm not very sure how components are affected by IPv6 and I'm not using IPv6, I think I'd better keep it enabled. By my past experience with Microsoft products, I've learnt that if one thing, A, is there before some configurations are applied, the process is quite automatic. But if A is missing before the configurations are applied, and I need to add A back, most of the time I need to apply configurations related to A MANUALLY. The problem is that it's not always sure if written form of such manual procedure exists, and even if it exists, it might exist in several versions and sometimes they are contradictory to each other. Here, I'm referring to IPv6 as A. So I decide to keep it. Hope I'm not making a bad choice.