Diagnose and resolve sending mail issue

I run a web hosting business, besides having been in IT for 15 years, so I have extensive mail delivery experience. The most common issue is DNS-related or sending directly from PHP (ends up being the same thing).

Does your server have any control panel on board?. I'm looking forwards to your response. Thank you.

Hello, Please let me know more information about server os and control Panel so that i can check and proceed further with the project. Thank you

Hello! I'm a Senior Linux Admin, with an background in email delivery. I have been working with Linux servers for the past 20+ years, and have deployed, configured and managed quite a number of email servers. I can troubleshoot and, as you put yourself, make it work no matter the difficulty of the issue or the price to be agreed, If too complex. I'm looking forward to the opportunity of doing this job. Best regards, Frederico

A proposal has not yet been provided

Hello, I would like at first introduce myself a little. My name is Ashot Aznauryan. I have 11 years of experience with different ISP and Hosting Providers. Also I have worked on various linux distributives (Centos, Debian, Ubuntu ...). for more info see my linkedin profile. Could you please provide more info what kind of mail server is installed.

Have worked with mail servers and all most of time in my company and resolve asap. I have 3+ years experience in that also.