Hi all, getting errors from SendGrid, and trying to figure out why, and how to get around them. We have already set up the white-listed domain and email associations. Here is the error:

Reason: 550 5.7.1 Unfortunately, messages from [IPAddresss Redacted] weren't sent. Please contact your Internet service provider since part of their network is on our block list (AS3140). You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors. [BL2NAM02FT026.eop-nam02.prod.protection.outlook.com].

 

Any help would be appreciated. Thanks!

Edit: yes, we are new to SendGrid, but we were using SparkPost with 0 issues before this. We changed because of the dropping of API support as well as SendGrid's api supporting 1000 emails per batch.

After less than a stellar response from their Support, we've moved back to SparkPost. It was just a "Well, you can upgrade to the 79.99$ plan to get your own dedicated IP..." and that was about it. We typically send out less than 300 emails per day...so I guess SparkPost with the SMTP option for 4.3 is fine for now. It's not worth the investment into SendGrid.