Exchange Mailflow Breaks on 1/1/2022 at 12:00 a.m. and the Y2k22 Bug

There is a major Bug on how some software stores the date/time of 1/1/2022.  Some software stores the date/time as a long integer variable.  The maximum value of a long integer variable is 2.147.483.647.  But when the date of is stored, systems break because this value is greater than the maximum allowed value of a long integer variable.  This Bug will impact any system that stores the date/time as a long integer variable.  As far as we know, it breaks mail flow on on-premise Exchange Servers and Mail Auditing and the Junk Box on the Sonicwall Email Security Appliance.


For Exchange, you have to bypass malware scanning on your Exchange Server to re-establish mail flow by issuing the following PowerShell commands:


  1. Get-ExchangeServer | % {Set-MalwareFilteringServer -BypassFiltering $true -Identity $_.Name} 
  2. Restart Transport service
  3. $ExchangeServers = Get-ExchangeServer | Select -ExpandProperty Name
  4. $ExchangeServers | % {Get-Service -ComputerName $_ -ServiceName MSExchangeTransport | Restart-Service -Force} 
  5. Restart the Exchange Front end Transport Service.
  6. Restart the Exchange Transport Service.


For SonicWall Email Security, a new version of the firmware will address this Bug – there currently is no workaround.


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