Different Unique Ids created using WebDAV and Exchange vs Outlook

Question

I am creating an appointment in Exchange via WebDAV, but the UId created is not the same as if I create the appointment in Outlook. The UId I believe is the same as the GlobalObjectId and should be unique and not change.

The UId if created via WebDAV is:

CD0000008B9511D182D800C04FB1625DDD67374428B4C644A0A359A2586E30B3

The UId if created through Outlook is:

040000008200E00074C5B7101A82E008000000002005332BA3A8CA01000000000000000010000000DD67374428B4C644A0A359A2586E30B3

If I open the appointment created via WebDAV in Outlook and then save it again the UId changes which is annoying (The UId changes to one above beginning with 04).

The second half of the UIds are the same GUID {DD673744-28B4-C644-A0A3-59A2586E30B3} and never change. The document here http://msdn.microsoft.com/en-us/library/cc425490 (EXCHG.80).aspx explains how the GlobalObjectId is constructed. Outlook seems to follow these rules, but Exchange doesn't. I am using Outlook 2007 and Exchange 2007.

There seems to be a myriad of different ids that can be used to identify appointments and I'm just looking for one that stays the same so I can track the appointment over time.

If anyone can help to explain why this UId changes or a way of creating it so it doesn't change it would be much appreciated. My limitations are supporting Exchange 2003 SP2 and Outlook 2003.

Answer 1

Oh yes Id can change, it can depend on the client and the way that you access the items. It a right PITA

I think the link may should help you though , (not knowing excatly what you are doing). There are mapi proerties that you can use as well but you may have to explain what you are doing a bit more ... are you only doing WebDav ?

http://stackoverflow.com/questions/934257/how-to-use-webdav-to-match-davhref-to-outolook-interop-href-value