DKIM på Office365 med Powershell

https://docs.microsoft.com/en-us/powershell/exchange/exchange-online/connect-to-exchange-online-powershell/connect-to-exchange-online-powershell?view=exchange-ps
https://docs.microsoft.com/en-us/office365/securitycompliance/use-dkim-to-validate-outbound-email#SetUpDKIMO365

http://www.mail-tester.com/spf-dkim-check (Her kan du få navnet på DNS CNAME record - selector1._domainkey.contoso.dk + ***)
https://mxtoolbox.com (tjek dkim opsætning - dkim:contoso.dk:selector1)


Start powershell som administrator, log på og indlæs PS Exchange extensions

Set-ExecutionPolicy RemoteSigned
Log på (O365 tenant credentials)
$UserCredential = Get-Credential

Indlæs PS Exchange extensions
$Session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://outlook.office365.com/powershell-liveid/ -Credential $UserCredential -Authentication Basic -AllowRedirection
Import-PSSession $Session -DisableNameChecking

Start dkim konfiguration
New-DkimSigningConfig -DomainName contoso.dk -Enabled $false (sætter dkim til Off - viser fejl hvis det allerede er off) 
Get-DkimSigningConfig -Identity contoso.dk | fl Selector1CNAME, Selector2CNAME           (*** den viser de records der skal oprettes)

Selector1CNAME : selector1-contoso-dk._domainkey.dkcontoso.onmicrosoft.com (navn selector1._domainkey.contoso.dk, FQDN selector1-contoso-dk._domainkey.dkcontoso.onmicrosoft.com)
Selector2CNAME : selector2-contoso-dk._domainkey.dkcontoso.onmicrosoft.com (navn selector2._domainkey.contoso.dk, FQDN selector2-contoso-dk._domainkey.dkcontoso.onmicrosoft.com)

Tilføj DNS records - tjek med http://www.mail-tester.com/spf-dkim-check  (bemærk at det kan tage lang tid før MS's DNS opdateres og brug output fra Get-DkimSigningConfig -Identity contoso.dk | fl Selector1CNAME, Selector2CNAME)

Set-DkimSigningConfig -Identity contoso.dk -Enabled $true
https://mxtoolbox.com (tjek dkim opsætning - dkim:contoso.dk:selector1)


Når færdig
Remove-PSSession $Session

Start DMARC opsætning

Tjek TLS på mailserver

https://www.checktls.com/

Hvis der er problemer, vil man ofte se at certifikatet er udløbet eller er self-signed

Free OCR software

Windows 10 app :
https://www.microsoft.com/da-dk/p/a9t9-free-ocr-software/9nblgggz5nsn?activetab=pivot:overviewtab

Windows program - også til GPO :
https://www.naps2.com/

Du kan også OCR genkende med OneNote

Check DKIM Office365

Powershell som administrator

Set-ExecutionPolicy RemoteSigned

winrm get winrm/config/client/auth (skal være Basic = true)

$UserCredential = Get-Credential

$Session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://outlook.office365.com/powershell-liveid/ -Credential $UserCredential -Authentication Basic -AllowRedirection

Import-PSSession $Session -DisableNameChecking


Get-DkimSigningConfig -Identity CONTOSO.DK | Format-List (dit domæne navn)


Remove-PSSession $Session

SPF, DKIM, DMARC

Test the Spammyness of youre-mails
https://www.mail-tester.com

Sørg for at emnefeltet har relevant indhold, f.eks. "Question about service provided) - ikke bare "Test" eller lign.
Selve e-mailen skal også have et relevant indhold, gerne en 25-50 ord (kopier en tekst fra et andet sted)

Check if your domain has these 2 email signatures set up and valid (DKIM)
https://www.mail-tester.com/spf-dkim-check

Selector = Selector1 og Selector2

dmarcian.eu
mxtoolbox.com DKIM:domain.dk:selectorX

https://docs.microsoft.com/en-us/powershell/exchange/exchange-online/connect-to-exchange-online-powershell/connect-to-exchange-online-powershell?view=exchange-ps

https://docs.microsoft.com/en-us/office365/securitycompliance/use-dkim-to-validate-outbound-email#SetUpDKIMO365

https://blogs.technet.microsoft.com/timmcmic/2018/02/09/office-365-spam-detection-and-reverse-dns-lookups/

Omgå Sophos tamper protection

https://community.sophos.com/kb/en-us/124377

Sophos ZAP

https://community.sophos.com/products/sophos-central/b/blog/posts/sophos-zap-is-now-available