Ha január 1-je után azt látjuk, hogy az Exchange szervereken állnak a levelek a küldési sorban, és az eventviewerben ezt látjuk:
“Error
The FIP-FS “Microsoft” Scan Engine failed to load. PID: 9244, Error Code: 0x80004005. Error Description: Can’t convert “2201010005” to long.”

A megoldást itt találjuk: https://aka.ms/ResetScanEngineVersion
Ezt a ps scriptet lefuttatva az alábbi outputot kapjuk:
[PS] C:\Program Files\Microsoft\Exchange Server\V15\Scripts>.\Reset-ScanEngineVersion.ps1
EXCH1 Stopping services...
EXCH1 Removing Microsoft engine folder...
EXCH1 Emptying metadata folder...
EXCH1 Starting services...
WARNING: Waiting for service 'Microsoft Filtering Management Service (FMS)' to start...
WARNING: Waiting for service 'Microsoft Filtering Management Service (FMS)' to start...
WARNING: Waiting for service 'Microsoft Filtering Management Service (FMS)' to start...
WARNING: Waiting for service 'Microsoft Filtering Management Service (FMS)' to start...
WARNING: Waiting for service 'Microsoft Exchange Transport (MSExchangeTransport)' to start...
EXCH1 Starting engine update...
Running as EXCH1-DOM\Administrator.
--------
Connecting to EXCH1.CONTOSO.com.
Dispatched remote command. Start-EngineUpdate -UpdatePath http://amupdatedl.microsoft.com/server/amupdate
További információ: https://techcommunity.microsoft.com/t5/exchange-team-blog/email-stuck-in-transport-queues/ba-p/3049447