How to install a certificate in Exchange Server? It's important to secure the Exchange Server…
How to create certificate in Exchange Server
How to create a certificate in Exchange Server? It’s important to secure the connections to Exchange Server with an SSL certificate. Let’s look at how to generate a certificate request, complete the certificate request, and assign the services to the certificate. Use the same steps in this article to renew a third-party certificate in Exchange Server.
Table of contents
- Create shared folder
- Create Exchange certificate
- Assign Exchange services to certificate
- Verify new Exchange certificate
- Copy certificate to another Exchange Server
- Renew Exchange Hybrid certificate
Create shared folder
Sign in to the Exchange Server. This can be the new Exchange Server or one that is already installed and configured. Create a folder on the (C:) drive and give it the name Certs. Right-click the Certs folder and share this folder.
Assign permissions to the folder:
- Your account (administrator) – Permissions Change/Read Allow
- SYSTEM – Permissions Change/Read Allow
Browse to the shared Cert folder path and verify that you can open the folder before proceeding to the next step.
Create Exchange certificate
Starting from Exchange Server 2016 CU23 and later and Exchange Server 2019 CU12 and later, the only option to create the Exchange certificate is with PowerShell (Exchange Management Shell).
Note: To prevent misuse of UNC paths by attackers, Microsoft removed the parameters that take UNC paths as inputs from the Exchange Server PowerShell cmdlets and the Exchange Admin Center. These changes will affect all cumulative update (CU) releases of Microsoft Exchange Server 2019 (CU12 and later) and Microsoft Exchange Server 2016 (CU23 and later). Read more in the article Exchange Server certificate changes.
Generate Exchange certificate request
Run Exchange Management Shell as administrator. Run the New-ExchangeCertificate cmdlet and fill in the details:
- Server: Specifies the Exchange Server to generate the request on.
- GenerateRequest: Prepares a 3rd party certificate request.
- FriendlyName: The friendly name of the certificate.
- PrivateKeyExportable: Allow you to export/import the certificate to other Exchange Servers.
- SubjectName: The subject field of the certificate request.
- DomainName: Specifies one or more FQDNs.
[PS] C:\>$txtrequest = New-ExchangeCertificate -Server "EX01-2019" -GenerateRequest -FriendlyName "Exchange Certificate 3rd party" -PrivateKeyExportable $true -SubjectName "c=NL, s=South Holland, l=The Hague, o=EXOIP, ou=IT, cn=mail.exoip.com" -DomainName mail.exoip.com,autodiscover.exoip.com
To create a wildcard certificate request, you should adjust the -SubjectName parameter and remove the -DomainName parameter.
[PS] C:\>$txtrequest = New-ExchangeCertificate -Server "EX01-2019" -GenerateRequest -FriendlyName "Exchange Certificate 3rd party" -PrivateKeyExportable $true -SubjectName "c=NL, s=South Holland, l=The Hague, o=EXOIP, ou=IT, cn=*.exoip.com"
Run the second command to export the certificate request to the shared folder.
[PS] C:\>[System.IO.File]::WriteAllBytes('\\ex01-2019\Certs\ExchangeCert.req', [System.Text.Encoding]::Unicode.GetBytes($txtrequest))
Sign in to Exchange Admin Center. Go to servers > certificates. Verify that you see the Exchange certificate with the Pending request status.
Process Exchange certificate request
Go to the shared folder and open ExchangeCert.req with Notepad.
Next, copy the certificate request.
Sign in to the third-party Certificate Authority. This can be any of your choices. Ensure that you select a multi-domain certificate because you have more than one domain name in the certificate.
Paste the copied certificate request and check that the CSR information is correct. It will show the company name and the domains.
Proceed further with the payment.
The Certificate Authority will ask you to validate the domain. This can be through an email sent to an email recipient listed on the domain registration or by adding a record in the public DNS.
Complete Exchange certificate request
The certificate is ready for you to download from the Certificate Authority. Download and unpack the certificate from the Certificate Authority to the Exchange Server shared folder.
Give the certificate an accessible name. In our example, the certificate name is Exoip.crt.
Run the Import-ExchangeCertificate cmdlet to complete the pending certificate.
[PS] C:\>Import-ExchangeCertificate -FileData ([System.IO.File]::ReadAllBytes('\\ex01-2019\Certs\Exoip.crt')) -PrivateKeyExportable:$true -Password (ConvertTo-SecureString -String 'P@ssw0rd1' -AsPlainText -Force)
The Exchange certificate will show the status Valid.
Assign Exchange services to certificate
Double-click the certificate and copy the certificate thumbprint.
Run the Enable-ExchangeCertificate cmdlet to assign services to the certificate. Fill in the thumbprint value which you copied.
[PS] C:\>Enable-ExchangeCertificate -Server "EX01-2019" -Thumbprint 6C31EB21621378CB5454A32F2DF0D1F87FAF69C5 -Services SMTP,IMAP,IIS -Force
Restart the Internet Information Services (IIS) on the Exchange Server.
Verify new Exchange certificate
Go to Outlook Web Access (OWA) URL or Exchange Admin Center (EAC) URL. Verify that the website connection is secure. Also, check that the Outlook client starts without any errors.
Copy certificate to another Exchange Server
Suppose you have more than one Exchange Server. Then you don’t have to do all the steps again. Instead, you can export the certificate and import it to the other Exchange Servers by following the below articles:
Renew Exchange Hybrid certificate
If you have an Exchange Hybrid environment, there are a couple more configurations. You must assign the third-party certificate to the Office 365/Microsoft 365 connectors. More on that in the article Renew certificate in Exchange Hybrid.
You learned how to create a certificate in Exchange Server. First, generate a certificate request. Next, complete the certificate request. As of last, assign the services to the certificate. The same steps apply when you want to renew an Exchange Server third-party certificate.
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This Post Has 16 Comments
If I have multiple domains, and want to have a multiple domain wildcard certificate, how can I add multiple wildcard domains in the certificate request?
Thank you for this article! It was very helpful.
It is amazing to me how difficult Microsoft has made this.
Hi dear Ali,
Thanks for your superb Exchange-how-to
After, We generate CSR by powershell, How can I find the private key? where is the path ?
The private key will be available after you run the Import-ExchangeCertificate cmdlet to complete the pending certificate.
You can create the certificate with mmc certificate snapin in the local computer personal store on the exchange server and it will show up in exchange 🙂
So no need to create it with ems.
Can you post how to remove the old cert either expired or not?
You can follow the below articles:
1. Remove certificate in Exchange Server
2. Remove Exchange certificate with PowerShell
А как удалить теперь этот сертификат?
I followed your instructions but after running the Import-ExchangeCertificate cmdlet to complete the pending certificate my certificate gets imported on the computer but EAC still shows status Pending request!!! It does not change to Valid. I run MMC and see my certificate is imported. It looks like cmdlet does not work as expected and my MS Exchange 2016 is not aware of new certificate. How do I fix this?
Before I never had trouble using EAC wizard for this. Is there any way to bring the wizard back? So much easier.
This can sometimes happen (it happened to me too). Do the steps again, and it should work.
Hi Ali, can you please let us know which SSL certificate you purchased? Thanks!
Hi Ali, Great Article as always. Noticed in CU23 EAC GUI it only has the option to Create a self-signed certificate and no longer has “Create a request for a certificate from a certification authority” Is this due to https://www.alitajran.com/exchange-server-certificate-changes/#h-exchange-admin-center-certificate-changes.
It’s now only possible to request a certificate from CA with PowerShell cmdlets, as shown in this article.
Poor Microsoft along time ago exchange 2010 had cool emc gui and now have only txt console like 30years ago msdos welcome back..
Excellent article!! I really appreciate you breaking all the tasks down in to easily understandable content. You are my go-to when I need to figure something out. Thank you, Ali.
Well Written Article with clear explanation. I think Exchange Engineer understand quickly but if someone learning exchange server this article good for them test VM ware again and again..