We start this scenario with a base Windows 2008 R2 SP1 Installation.

Funny that, eh? Install Exchange 2007 Sans RPC/HTTP Since Exchange 2007’s Outlook Anywhere requires the RPC/HTTP component, it will not work without it. This is the RPC/HTTP proxy component that was introduced in Windows 2003 and allowed for the introduction of RPC/HTTPS. It is possible to install Exchange 2007 and enable Outlook Anywhere without installing the required underlying OS component. Note that enabling OA on the legacy Exchange servers is not a requirement unless you want to start using OA for legacy mailboxes as well as Exchange 2013 mailboxes. You may receive EventID 2003 stating that the RPC over HTTP proxy component is not installed of is not configured correctly. Since some customers may not already have Outlook Anywhere (OA) enabled, and are lighting it up to permit co-existence with Exchange 2013, they may run into issues if the required OS bits are not deployed on the older versions of Exchange.

Update 16-6-2016: Updated PowerShell Example to use code formatting, and to also set client auth to be NTLM. Update 12-11-2014: Updated reference for disabling IPv6 Update 12-11-2014: Updated reference to OA traffic flow from Gavin's feedback. Update 27-3-2014: Added link to TechEd 2013 Outlook Anywhere session. After walking through the scenario we will see what can be done about it and review a couple of other issues that will probably crop up, for example IIS permissions. Let's look at an issue that can arise in an Outlook Anywhere co-existence scenario with Exchange 20. Exchange 2013 can be deployed into an existing Exchange organisation where Exchange 2007 SP3 RU10 + and/or Exchange 2010 SP3 exists. Since we are still in the early stages of the year, and Exchange 2013 SP1 is now available, we will see lots of migrations to Exchange 2013.

Outlook exchange 2013