Exchange 2003 NDR when sending to internal users

[HaierIT]

Hello to all, I am having a weird issue and it only happens intermitenlly with about 4 people in total. These users are emailing users within our company and getting NDR. It only happens sometimes which makes it harder to figure out. I checked spelling and email address is correct. It works most times but every so often they get this message.

NDR Reads:
The e-mail account does not exist at the organization this message was sent to. Check the e-mail address, or contact the recipient directly to find out the correct address.
<mail.Company.com #5.1.1>

What can possibility be the issue when emailing someone in your own company.

 

[ShackDaddy]

I would clean up the .nk2 file of each of those four users, getting rid of any saved aliases for each other, and also find any similar objects in their personal contacts that refer to each other and delete them. It's possible that this happens depending on how they go about retrieving the email address (autocomplete, reply, contacts, etc), and sometimes it pulls it from a bad source.

With something else in mind: how many domain controllers in your organization?

Dave Shackelford
ThirdTier.net
TrainSignal.com

 

[Zelandakh]

Is that sending TO these 4 people or them sending out?

Update the OAB for everyone. As Dave says, sort out the nk2 file / suggested contacts (depends on the outlook version).