Email Server Error message issue
I have an email server which I use to server for sending emails.
Some of my clients are reporting me this error as in the image.
I have checked my server thoroughly ,there is nothing wrong with it or its settings.
Many other clients are sending mails smoothly ,but those who are reporting this error problem, I visited them myself and tried to send email from them to the server and entered all information correctly including the server name, but it gives the same error on their computers.
So I don’t want my clients down anyway .I rested their account on my server and made some changed the server name and then asked all clients to send mails with this server name , but again those who were sending before could send now too, but the problem was still there with the same clients.
Can please someone help me out with this problem.
To enable SMTP Mail you must enter a valid mail server name.