[kenw]

I have an interesting problem where my iPhone causes emails to vanish. This morning my iPhone rang to tell me an email had arrived. I waited at my Mac for the email to arrive there, but it never showed up. So I went to my iPhone and checked the Inbox. There was a new message, but after reading From and Subject, the message simply vanished. There is no trace of it in the Trash or any other folder on the iPhone, and it never showed up at my Mac Mail or on web mail. This has happened 4-5 times over the last few months (as far as I know). As far as I can tell, all the vanished emails have come from only two organizations, one of them being IBM. If I alert the sender that their email vanished, they send a repeat message and that comes through fine. One organization simultaneously sends email to my corporate email account, and those always come through OK. Any ideas what is causing this? I can't find any references to this problem on Google.

[JKT]

Being marked as Junk, and then filtered out perhaps? (Do you have a rule set up to automatically delete junk mails in Mail?).

What type of account is this on - IMAP or POP or other?

[kenw]

You may have hit on something. This is a standard MobileMe account. I do have one rather complicated rule that is set to delete messages. As far as I can tell, the rule should not have affected the messages that vanished, but perhaps it did. In any event, I had assumed that when a rule is set to Delete a message, it would send the message to the trash. After some experiments, I realize that Delete actually makes the email vanish with no trace, which is exactly what I am seeing. So it is possible that the iPhone receives an email before the Mac has a chance to filter it (I assume the filtering is done on the Mac). Then while I am looking at the email on the iPhone, the phone syncs with the Mac and makes the email vanish. For now, this is my working hypothesis. Thanks for the comment.

[JKT]

It is probably what is happening - for mails that get pushed to my iPhone they sometimes appear and then disappear almost instantaneously because the desktop app is open and just happens to be in the process of downloading the mail then applying its rules at roughly the same time as my phone.