Microsoft Exchange Hybrid Management
Microsoft Exchange: Microsoft messaging and collaboration software.Hybrid Management: Organizing, handling, directing or controlling hybrid deployments.
2,130 questions
O365 to Exchange 2019 on prem emails stuck
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JohnMark Mulli
0
Reputation points
Hi,
Have an office 2019 and Office365 hybrid environment. Emails from O365 to exchange on prem getting stuck on O365 side with error Reason: [{LED=450 4.4.317 Cannot connect to remote server [Message=451 4.4.0 Security status IllegalMessage].
Has been working okay just suddenly stopped. what could be issue?
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