Exchange 2016/2019 Email Stuck in Transport Queues

After the new year an issue has been identified with the malware scanning system built into Exchange 2016/2019 with messages being stuck in transport queues on Exchange Server 2016 and Exchange Server 2019 because of a latent date issue in a signature file used by the malware scanning engine within Exchange Server. When the issue occurs, you’ll see errors in the Application event log on the Exchange Server, specifically event 5300 and 1106 (FIPFS)

Workaround

Bypass the Anti-Malware Engine using the following commands in the Exchange Management Shell:

Set-MalwareFilteringServer -Identity “ServerName” -BypassFiltering $true

Restart-Service MSExchangeTransport