Outlook Addin 2010 Issue with downloading (c# only)

Question

Hi All,

I am writing  in outlook plugin 2010 such that  it downloads Email which has attachment . Email comes Daily at 6 and gets downloaded into a Folder,problem comes on Monday when I open my laptop I see 3 mails from Sat, Sun , Monday. And I see that the Attachment Downloaded is only for Saturday's (not latest Monday). I saw that some one told me to use "Mark as Download" Property in outlook to check whether it has downloaded or not and get latest attachment that is on Monday. Can some please help me a syntax or EXAMPLE in C# for Mark as downloaded property.

I have googled for mark as download it is showing me VB only an example for c# would be good .Please provide me this help.


I have also attached my code, please have a look