https://supertekboy.com/2023/07/08/renew-a-certificate-in-exchange-2016-2019/

POWER SHELL

**GET THE THUMBPRINT OF THE CURRENT CERT.
Get-ExchangeCertificate | Where {$_.IsSelfSigned -eq $false} | Format-List FriendlyName, CertificateDomains, Thumbprint, NotAfter

**MAKE CERT REQUEST FROM PROPER CERT.
$certrequest = Get-ExchangeCertificate -Thumbprint XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX | New-ExchangeCertificate -GenerateRequest -PrivateKeyExportable:$true

[System.IO.File]::WriteAllBytes('c:\cert\certrequest.txt', [System.Text.Encoding]::Unicode.GetBytes($certrequest))

**IMPORT THE NEW CERT INTO THE SYSTEM
Import-ExchangeCertificate -FriendlyName remote.lewarkmetalspinning.com -FileData ([System.IO.File]::ReadAllBytes('c:\cert\NAMEOFCERT.cer')) -PrivateKeyExportable $true

**GET THE THUMBPRINT OF THE NEW CERT.

Get-ExchangeCertificate | Where {$_.IsSelfSigned -eq $false} | Format-List FriendlyName, CertificateDomains, Thumbprint, NotAfter

Enable-ExchangeCertificate -Server EX19-01 –Thumbprint XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX –Services IIS,SMTP

**REMOVE THE OLD CERT.
Remove-ExchangeCertificate -Server EX19-01 -Thumbprint XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX