We are seeing this:

Log Name: Application
Source: MSExchangeTransport
Date: 06/12/2018 22:19:07
Event ID: 1035
Task Category: SmtpReceive
Level: Warning
Keywords: Classic
User: N/A
Computer: %computername%.domain.suffix
Description:
Inbound authentication failed with error LogonDenied for Receive connector Client %computername%. The authentication mechanism is Ntlm. The source IP address of the client who tried to authenticate to Microsoft Exchange is [IP Address].
Event Xml:



1035
3
1
0x80000000000000

896299
Application
%computername%.domain.suffix



LogonDenied
Client %computername%
Ntlm
IP Address



But the machine mentioned should have permissions - what do we need to do to enable this relay?

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