Delegates / Proxy Migration in Exchange 2007 sp1

One thing we notice is that folks sometimes want to have their Proxies (Meeting Maker term) or Designates (Oracle Calendar Server term) migrated into Exchange 2007 as Delegates (Outlook term).

For Exchange 2007 before sp1 you were out of luck. For Exchange 2003 you only need to use CDO 1.21 with documented memory leaks. Those of you for whom we have migrated Proxies know this is why the process to migrate proxies takes almost as long as the process to migrate your calendar data. And annoyingly CDO 1.21 is not supported at all in .NET code.

For E2K7 sp1, Microsoft documentation gives you the impression this is possible using only Exchange Web Services. DeVa expands on this a bit in Adding delegates in Exchange Web Services (sp1).

However, our direct experience with a recent client migration to E2K7 sp1 and Glen (whom we cannot praise too much) confirm that setting permissions via Exchange Web Services is insufficient. You also need to set permissions on the Schedule+ NON_IPM_SUBTREE.

Wait you say -- this is 2008 and I just saw the word "Schedule+" appear in print, like it was... 1992 or something. Is this possible?

Rest assured, it is mos def.

In fact at least one user has reported a problem and documented a solution in in this data structure during a migrating from Exchange 2003 to Exchange 2007. Microsoft seems to have picked up on this in KB 945602.

For those of you who want a fuller story on how Delegates relate to the Free/Busy folder, thank Ximian for their work in reverse-engineering and publishing the results (which they did for E2K3).

So the end result here: be really careful writing scripts to set Delegates for calendar functions in Exchange 2007 and make sure you take into account the NON_IPM_SUBTREE in addition to the documented EWS code.

And, this being Exchange, there are additional complications because .... well.... because Exchange is clearly built by committee. So if you have BOTH Outlook 2003 and Outlook 2007, and use Delegate (and I'll bet the answer is "yes" all around), you need to check out KB 924470. While you're at it -- these also give you some idea how funky basic Delegate functioning is in E2K7: KB 950794, KB 918797, KB 932207, and KB 942418.

Does it work or not? This is so convoluted we're not sure. If any of you have feedback let us know.