E-mail from Exchange server being flagged as spam

[nsherin]

Hi all,

 

I've recently set up an old Dell Optiplex running Windows Server 2003 and Exchange 2003 at home for home file server duties, as well as providing a place to host web/e-mail service for my domain.

 

All was well for about a week or so, then over the last few days, e-mail sent to others seems to get rejected or flagged as spam by recipient mail servers. A friend noticed that when I sent him an e-mail to his Hotmail account, my message got flagged as junk. I have just tested with my Google Mail account and mail that gets sent to there is also flagged as spam.

 

I have checked to see if my domain or IP address is blacklisted using MX Lookup Tool - Check your DNS MX Records online - MxToolbox and all looks well.

 

Does anybody have any ideas as to what the hell could be causing this and how to fix it?

 

Any help is much appreciated!

 

Cheers,

Neil

[john]

you need to ensure all your MX records, IP Records etc all tally up and match 110% perfectly. So your IP on your internet connect must resolve to your name of your mail server eg:

 

your static IP: 12.34.56.78 needs to resolve to server.yourdomain.com

and server.yourdomain.com needs to resolve to the ip - 12.34.56.78

 

You also need to make sure your Exchange box responds the requests with that same name, no .locals or things like that.

 

Hotmail, Gmail etc are all very fussy, but everything must match at all angles. MS have a guide somewhere to advise on how to ensure your mailserver doesn't get blocked / flagged as junk to start with.

[FN-GM]

are you using a dynamic public IP address? If so this will be the reason.

[nsherin]

Nope - I have a static IP with the MX record and DNS entries for my domain pointing to it.

[Michael]

Have a read through Microsoft's guidelines and see if this helps. Interestingly it could be something as simple as not accepting e-mail from senders who fail a reverse-DNS lookup.

[john]

Have a read through Microsoft's guidelines and see if this helps. Interestingly it could be something as simple as not accepting e-mail from senders who fail a reverse-DNS lookup.

Thats what I failed on first one I did, this is quite key for MS.

[nsherin]

Thanks for all the advice thus far. Have checked MS's guidelines and cannot see anything that should be causing the problem. Any other ideas would be much appreciated.