I am experiencing something similar. I have sent the relevant server logs to the helpdesk, but have not heard anything yet.
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+-------------------------------------------+
|            Michael Surato                 |
|      College of Arts and Letters          |
|      Michigan State University            |
|            320 Linton Hall                |
|        East Lansing, MI 48824             |
| Voice: (517) 353-0778 Fax: (517) 355-0159 |
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>>> On 1/21/2009 at 2:50 PM, Jon Galbreath <[log in to unmask]> wrote:
> Has anyone else had any users complaining of mail that never gets delivered?  
> I've only had one user so far, but unfortunately, I can kind of confirm his 
> issue, so I have to look into it.
> 
> He's only said that people are calling him because he hasn't responded to 
> mail that they sent him, but he apparently has never gotten.  I should note 
> that this is off-campus mail that is falling into a black hole.
> 
> We're running Exchange here, so mail is forwarded in from MSU's servers via 
> the standard forwarding in the web interface.  Mail within the Exchange org 
> is working fine, as is most mail from the outside.
> 
> I did a few tests sending mail to myself from Yahoo and Gmail and they came 
> through instantly.  However, when I sent a couple messages to myself from my 
> Exchange server at home, they never showed.  But when I replied to a message 
> I'd sent myself yesterday, it showed up instantly here.  Per the Exchange 
> logs, the messages have never hit our servers.  Nor have I gotten any NDRs 
> sent back to me.
> 
> I'm waiting for the user to get back to me with approximate times and 
> domains that he's missing mail from, but I thought I'd check if anyone else 
> is having issues.
> 
> Thanks!
> Jon
> 
> Jon Galbreath
> MCSE/Security+
> Systems Administrator
> International Studies and Programs
> Ph: 517-884-2144
> [log in to unmask]<mailto:[log in to unmask]>