Open Specific MailItem in Outlook from C#

Question

I want to open a specific email in Outlook from my C# winforms application.

At the moment I have got the following code:

//...Get Folder & Entry ID for last Email in Sent Box

Outlook.Application myApp = new Outlook.ApplicationClass();
Outlook.NameSpace mapiNameSpace = myApp.GetNamespace("MAPI");
Outlook.MAPIFolder mySentBox = mapiNameSpace.GetDefaultFolder(Outlook.OlDefaultFolders.olFolderSentMail);                
Outlook.MailItem myMail = ((Outlook.MailItem)mySentBox.Items[1]);
string guid = myMail.EntryID;
string folderEntryID = mySentBox.EntryID;
string folderStoreID = mySentBox.StoreID;
string mailAddressee = myMail.To;
MessageBox.Show(mailAddressee);

//...Attempt to Open that Email at a later date

Outlook.MAPIFolder getFolder = (Outlook.MAPIFolder)mapiNameSpace.GetFolderFromID(folderEntryID, folderStoreID);
Outlook.MailItem getItem = (Outlook.MailItem)getFolder.Items.Find("[EntryID] = " + guid);
getItem.Display();

The first an second parts of the code will be run at different times, although they are in the same Method for testing at the moment.

The first part obtains the relevant IDs for the mst recently sent email from Outlook. This part seems to work fine as evidence my the Messagebox I've built in.

The second part however is not working and I'm struggling to find the right code to access and open that specific mailItem having obtained its ID and folder location in the first part.

Anyone able to complete this little project for me please.

Answer 1

Done it at last by replacing the following lines of code . . .

Outlook.MAPIFolder getFolder = (Outlook.MAPIFolder)mapiNameSpace.GetFolderFromID(folderEntryID, folderStoreID);
Outlook.MailItem getItem = (Outlook.MailItem)getFolder.Items.Find("[EntryID] = " + guid);

with this . . .

Outlook.MailItem getItem = (Outlook.MailItem)mapiNameSpace.GetItemFromID(guid, folderStoreID);

Answer 2

You can not use EntryId with the _Items.Find method. The MSDN reference is here.

There is also a remark which could be interesting for your project:

"The Entry ID changes when an item is moved into another store, for example, from your Inbox to a Microsoft Exchange Server public folder, or from one Personal Folders (.pst) file to another .pst file. Solutions should not depend on the EntryID property to be unique unless items will not be moved."

MailItem.EntryID Property (Outlook).