Last week encounter a problem, now solved, but people think this process is worth sharing with do-mail maintenance.
Suddenly received a letter back saying users, and these users are users on the Exchange server, they actually can not give cloud users on their company mail. My error was to give a shot, no valuable information.
In such problems, the first time I logged O365 management side of (our mail environment is a hybrid deployment), the mail flow, message trace, the sender and recipient information to fill in, then search
Actually the conclusion is Delivered
Later, I got some bounce log from a local IT, which has a very useful.
When I saw here, I subconsciously reflects is filtered. As a relatively senior people immediately go here to check. https://mxtoolbox.com/blacklists.aspx
above this site we hope to be saved.
The results found that really in the blacklist. Solution is of course to call that spamhaus apply to mention, this site is a little pit, you will find in the country to access some of the content will not show, because we use the framework of this site visit is not displayed. Headquarters with the assistance of colleagues, put a bit applications, and then receive the confirmation email, put our name removed from the list.
In fact, there is a way to solve this problem is to create a new Send connector, out of local, do not take Microsoft cloud Send connector, but the company's mail flow is centrally managed, they still do by the old rules.
If the two companies send each other e-mail problems, from this point of view there is not a domain name is filtered, to solve this problem most important thing is to look at the log, but also have a clear idea of solving the problem.