For the last few weeks I’ve had an odd problem with mail sent from my Treo. The solution ended up being unexpected.
I carry a Treo 700w pretty much everywhere I go. It’s connected via Exchange ActiveSync to my home Exchange server and via IMAP to my server at 3Sharp. Combined with Entourage (and Pocket Outlook’s ability to accept a meeting invite on an IMAP account and put it in the main calendar) this gives me on-the-go access to pretty much everything I need. However, since December or so I haven’t been able to send from my 3Sharp account to some recipients, or so I thought.
This morning I finally got irritated enough to figure out what the problem was. Turns out it was the GRYNX greylist tool Devin implemented back in November. For some reason, it had decided that mail coming from some IPs (including the entire Verizon Wireless network) should be greylisted if the message contained more than one recipient. I guess this was expected behavior, since that’s what a greylisting tool does.
The oddest thing is that I’d get an NDR message on my Treo telling me that there was an invalid recipient and that the message had been filed in the Drafts folder. This was a result of Pocket Outlook attempting to be helpful, but its message didn’t really tell me what I needed to know.
I verified that this was the problem by using telnet from my desktop to log in, issue AUTH LOGIN, and try to send a message with one recipient– worked great. I then did the same thing with two recipients and boom! I got grey. The fix was trivial: I had to add my sender address to the greylist whitelist (huh? did I just say that?) and now mail is working properly.
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