On January 1 2022, most on-premises Microsoft Exchange servers stopped sending and receiving email.
This was due to a coding decision to store dates as an integer and this value max’d out on Jan 1 2022.
Fortunately Microsoft have released a fix for this.
The fix is detailed in this link with instructions.
Microsoft Exchange Y22K bug fix – Using the Automated Solution
- Download the script here: https://aka.ms/ResetScanEngineVersion
- Before running the script, change the execution policy for PowerShell scripts by running Set-ExecutionPolicy -ExecutionPolicy RemoteSigned.
- Run the script on each Exchange mailbox server that downloads antimalware updates in your organization (use elevated Exchange Management Shell).
Edge Transport servers are unaffected by this issue. You can run this script on multiple servers in parallel. After the script has completed, you will see the following output:
[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.
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Connecting to EXCH1.CONTOSO.com.
Dispatched remote command. Start-EngineUpdate -UpdatePath http://amupdatedl.microsoft.com/server/amupdate
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[PS] Add-PSSnapin Microsoft.Forefront.Filtering.Management.Powershell.
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[PS] C:\Program Files\Microsoft\Exchange Server\V15\Scripts>Get-EngineUpdateInformation
Engine : Microsoft
LastChecked : 01/01/2022 08:58:22 PM -08:00
LastUpdated : 01/01/2022 08:58:31 PM -08:00
EngineVersion : 1.1.18800.4
SignatureVersion : 1.355.1227.0
SignatureDateTime : 01/01/2022 03:29:06 AM -08:00
UpdateVersion : 2112330001 (note: higher version number starting with 211233... is also OK)
UpdateStatus : UpdateAttemptSuccessful
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