We have an application (.NET 2.0) that uses Outlook 2003 features (Microsoft Office 11.0 Object Library). My new computer has Windows 7 and Office 2010 installed, and the references don't work anymore (there's only Office 14 Object Library available).
Is there any way to use Office 2003 dlls when Office 2010 is installed (I've heard that 2003 and 2010 cannot be installed on the same machine)? I've tried to install the "Redistributable Primary Interop Assemblies" for Office 2003, but couldn't do it without installed Office 2003.
Rather that referencing a specific version of the libraries, use late binding. That way you can develop against one version, but as long as you stick to using common functionality it'll work in other versions as well.
This article explains the difference Binding for Office automation servers with Visual C# .NET
It can be easier to do the development using early binding so that you get Intellisense and then removing the references later on (which will take a little time. If it's worth itdepends a bit on your skill level with Office development.