Blocked Emails

[helsknight]

We recently install exchange 2003 and started to host our email internally. Previous to that we had our ISP host our email domain. We are finding that a few domains out there are blocking our emails.

Examples:

xxx@att.net on 4/22/2008 8:48 AM
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
<ourdomain.com #5.5.0 smtp;550-xx.xx.xx.xx blocked by ldapu=rblmx,dc=worldnet,dc=att,dc=net>

and

xxxx@earthlink.net on 4/21/2008 4:53 PM
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
<ourdomain.com #5.5.0 smtp;550 550 Dynamic/zombied/spam IPs blocked. Write blockedbyearthlink@abuse.earthlink.net>

Aside from trying to contact att and earthlink about the blockage. What else can I do? Any help is appriciated.

-Bee

 

[noveyron]

Check to see if your domain is on any dns blacklists

http://www.mxtoolbox.com/blacklists.aspx

Do you have a reverse DNS record set up? If no, you need to get on the case pretty sharpish.

 

[cmeagan656]

Also make sure that you have an SPF record.

Are you routing your outgoing mail through your ISPs servers? If not then some ISPs will block you.

Cheers.