W had a third party server which was relaying messages to external domains.Now since the subscription has ended i was trying to relay mails through may mail server.Few domains are not accepting my mails and bouncing
550:mailbox not available
Initially i thought issue was with reverse PTR entry and fixed it with help of ISP.Still lot of domains are not accepting my mails when relayed through my mail server.
Can someone help me in fixing this issue? I'm ready to provide the logs if required.