Not getting all Emails

[vincet]

Just in the last couple of weeks, one of our vendor suddenly is having problem sending email to me. They can receive our emails without any problem. When they send us email however, we never get it any they get " Recipient's server exceeded time for connection". They are able to do a nslookup to our exchange server, and they are also able to ping us. So far, this is the only domain that I know of that is having problem sending to us. Anyone got any idea as to what I should be looking for?

Thanks
Vince

 

[shrubble]

Have you messed with your firewall or any SPAM filters lately (i.e. did anyone there write one from scratch?)?

Do any of your logs show any evidence of the attempted connection?

Are you sure that they are the only ones having this problem?

Have you changed ISPs or altered any network appliances recently?

Are THEY sure that you're the only domain that THEY can't send mail to ('cause it very well may be their problem!)

If a tree falls in the forest and no one is around to hear it, did it make a sound? (sorry- had to throw that one in!)

deletion mistake
no I can't recover that
you didn't save it

-Shrubble

http://www.ishrubble.com

 

[vincet]

No changes to the firewall or SPAM filter. In fact, FW is one of the first thing I checked. I have not been able to decipher the log yet so that is the next I will try to tackle. No changes in ISP or any network appliances at all (from both side). I am not sure if they are the only domain that I am having problem with, as far as I know, they are the only one but again, can't really say with 100% certainty. Their ISP did a telnet connection to my exchange and got connected. So connectivity wise, it seems to be working.

Any other ideas?

Thanks
Vince

 

[shrubble]

http://pobox.com/bounce-common.mhtml

deletion mistake
no I can't recover that
you didn't save it

-Shrubble

http://www.ishrubble.com