Supporting Outlook 2003 and 2007 at the same time with interop

Question

Is it possible to access Outlook 2003 and 2007 from the same application, using the primary interop assemblies provided by Microsoft?

I have read that it is very difficult (if possible at all) to develop for different versions of Outlook on the same machine, because of the way COM versioning is handled. Are we better off using Outlook Redemption if we want to support multiple versions?

Answer 1

I suppose it is better to create a COM (or .net) library which acts as an interface or entry point for all your needs. It will be better to have an interface assembly & 2 concrete assemblies (implementing interfaces) one for each Outlook version.

This will save you from inconsistencies in OOM behviour for different versions.

Redemption serves that purpose. But, it is used primarily to avoid security prompts that are raised by Outlook (when one tries to read something from existing email/addressbook that is considered vulnerability). Redemption reads the underlying MAPI database, which is also used by OOM.