I'd like to use Public Folders for storing e-mail, so that each distribution group would have a corresponding mail-enabled Public Folder. Mail might originate from outside of the Exchange organization, so the Public Folder would need to accept mail from *anyone*. Thus (I think), it would need to be writeable by anyone. [Correct me if I'm wrong.] I'd like to restrict such Public Folders so that *only* e-mail messages could be placed in them. I don't know if that's possible. If I select "Mail and Post" as the type of items that are permitted, I can still drag files into the folder. Is there magic that can be invoked to make the Public Folder be a "mail-only" container? Or do I give up and use a Shared Mailbox instead? The server is Exchange Server 2007 SP3. Thanks, ..Jeff

If you set the Default to Reviewer only and anonymous to contributor, does it work as expected?

With 'anonymous' as Contributor, neither e-mail from outside Exchange nor inside Exchange works. I think it's also interesting that with those settings, I can't copy files into the folder, either. I suppose that since I am authenticated, the "anonymous" permissions don't apply.

Anonymous as contributor should work for externally sent mail.

Thanks, but it doesn't for me. I'm wondering about the identity of the potential "writer" of the public folder in this case. An external SMTP server delivers a piece of mail to my Hub Transport server, which hands it off to a mailbox server to store in a Public Folder. At that point, is the user who's trying to write the mailbox really "Anonymous", or is it "network service" or something else? I'm thinking that it's not really anonymous. Of course, for our purposes, it seems that "Everyone" has to be a contributor. My original question was whether there was any way to prevent people from placing non-mail items into the folder, which is what I'm most concerned about.

Anonymous depends on how the message was received by Exchange. If the sending client authenticated to the server ( mapi,OWA , through a receive connector, or a SMTP gateway that authenticates ) then its not anonymous. I think for the original question, I prefer mailboxes because pfs are too quirky IMO. But I think you could experiment a bit and get it work as you want with a pf.

Per my research, there’s no method that can restrict the message type on the public folder on the exchange natively. Please use mailbox as workaround Andy’s right about the permission of anonymous account. Please create a new public folder and mail-enable it, see if the mail flow works. Anonymous group should only have “CreateItems“ right on the newly created public folder “To ensure that users can send e-mail messages to a mail-enabled public folder, the public folder must have at least the CreateItems access right granted to the Anonymous account” --------Refer to <Configuring Public Folder Permissions>James Luo TechNet Subscriber Support (http://technet.microsoft.com/en-us/subscriptions/ms788697.aspx) If you have any feedback on our support, please contact tngfb@microsoft.com