How to determine where a Mailitem is being opened from in Outlook 2007 using VSTO 2005 SE

Question

I have an Outlook 2007 Add-in in VSTO 2005 SE that allows users to save e-mails into our document management system. From within our system users are able to open e-mails they have previously saved. However, when doing so I need to try and prevent them from saving them again.

I am trying to figure out how to determine if the Mailitem being opened is coming from the Outlook e-mail client or from an external source.

I know that normally the EntryId Property of the Mailitem is null or empty string when a Mailitem has not been previously saved in Outlook, however, it seems like when a Mailitem is being opened from within our system the EntryID is not null.

Answer 1

Adam, Normally most DM systems set mapi properties or user properties on the mail items as they get saved ... DOCID etc. from the DM system. I would get outlook spy and hunt around on the DM emails to try and find this Property. Then you will be able to test for that in your VSTO add in. Failing that, may be you can explain how you open the email from you DM system is from inside outlook via a DM plug in ? or is it totally external app? What DM System is it ? Marcus