I have installed the Connection Filtering agent:
Install-TransportAgent -Name "Connection Filtering Agent" -TransportService FrontEnd -TransportAgentFactory"Microsoft.Exchange.Transport.Agent.ConnectionFiltering.ConnectionFilteringAgentFactory" -AssemblyPath "C:\Program Files\Microsoft\Exchange Server\V15\TransportRoles\agents\Hygiene\Microsoft.Exchange.Transport.Agent.Hygiene.dll"
Add-IPBlockListProvider -Name zen.spamhaus.org -LookupDomain zen.spamhaus.org -AnyMatch $true -Enabled $true
Enable-TransportAgent -TransportService FrontEnd -Identity "Connection Filtering Agent"
Restart-Service MSExchangeFrontEndTransport
After this, it doesn't work. Email from ip addresses marked as blacklisted (as can be seen by test-ipblocklistprovider) aren't blocked. Besides, no logging is created in “C:\Program Files\Microsoft\Exchange Server\V15\TransportRoles\Logs\FrontEnd\AgentLog”
Get-AgentLog -TransportService Frontend gives a warning: WARNING: An unexpected error has occurred and a Watson dump is being generated: Index (zero based) must be greater than or equal to zero and less than the size of the argument list.Specified cast is not valid.
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