blacklist exchange
Hello there; We use Exchange mail server. All our dns records are available including DMARC and DKIM. However, even though we are not in any Blacklist, some of our customers try to send e-mails as follows and not receive mails. With "sorbs.net", we have emailed many times and stated that they do not come from their own address and that our ip addresses are not in their database and that we call the problem in the outside world by showing a few examples. But they didn't come up with a solution. For example: any one can send an e-mail to a yahma or yahoodan company e-mail address, while the other person cannot assign and give the following error. The next day or 2 hours later, when you try, it freezes to normal, but then it gets back to its normal state for a while. Has any of these problems come up and found a solution? Thank you. "550 5.7.1 Your IP is on the sorbs.net block list"