HELO command issue "_"

[GellyBelly]

I have an exchange server 5.5 and

An administrator from another company is trouble shooting why I can't send emails to his server. He says the HELO command that my SMTP server is sending has an underscore ("_") that is incompatable with his new server (whatever that may be). The header reads as follows:

Received: from mail.mycompany.com ([XX6.2X4.1Xx.3] helo=nt_server.mycompany.com)

1) Has anyone ever heard of this problem?
2) Where would I change "nt_server" to say "Ntserver"

My server is named "NT_SERVER". Is it at that level or is the HELO command picking it up from somewhere else?(hopefully)

Thanks

Gerry

 

[zbnet]

Underscores are NOT allowed in DNS server names - you're NT server name is plain wrong if you want to expose it to the Internet.

Unfortunately once you have Exchange on a server you can't rename it. You have to remove Exchange first, rename it, then reinstall Exchange, then restore your DBs.

It would probably be easier to add another server to your org and install the IMS on that one instead. Make sure you don't use an underscore in the server name...

 

[GellyBelly]

Hello,

Thanks for your response.

Please elaborate why the "NT_SERVER" name is "plain wrong".
The server has been managing email since the beginning of time. My question pertains to the "_" Are you saying the "_" is incorrect? Underscores have been used in names, descriptions,labels, etc also since the begginning of the computer age.

Wow! It takes that much to change the name of an exchange server??!!

 

[zbnet]

I don't know how to say it more clearly: some Unix-based SMTP servers refuse connections from SMTP servers that introduce themselves with a FQDN that includes an underscore. So if your IMS server name includes an underscore, you're asking for trouble.

The true DNS spec has never allowed underscores in host names. Microsoft's implementation does, for varous historical reasons, but that doesn't mean you should use them - DNS has been around for a lot longer than Exchange!

Yes, unfortunately that really is the way to rename an Exchange server - the name of the server is very tightly bound into the Directory on the server.