Qlik Sense - Qlik Sense Repository Service does not start after removing the Qlik Sense Certificate from the MMC

After removing the certificates (QlikClient, Server, root) and restarting the Qlik Sense services, the repository does not startup anymore.

Looking into the Qlik Sense Repository Security logs (By default: C:\ProgramData\Qlik\Sense\Log\Repository\Trace\Servername_Security_Repository.txt), you might find an error looking like this: 

ERROR    QlikServer1    Security.Repository.Qlik.Sense.Common.Security.Cryptography.SecretsKey    11    ced918f0-3cbf-45be-938b-44cfa13a5202    DOMAIN\qvservice    When retrieving symmetric key from cert:     Object reference not set to an instance of an object.       at Qlik.Sense.Common.Security.Cryptography.CryptoSupport.GetPrivateKey(DotNetCert cert)↵↓   at Qlik.Sense.Common.Security.Cryptography.SecretsKey.<>c__DisplayClass5_0.<RetrieveKeyFrom>b__0()↵↓   at Qlik.Sense.Common.Logging.LogExtension.WrapLog[T](IQSLog log, String actionDescription, Func`1 action)

The Qlik Sense Repository System logs (By default: C:\ProgramData\Qlik\Sense\Log\Repository\Trace\Servername_System_Repository.txt) may show the repository stuck on this event: 

INFO    QlikServer1    System.Repository.Repository.Core.Services.SetupService    11    42c08161-967d-4a98-91b7-2fba7b6327fd    DOMAIN\qvservice    Setup service initialized with 2 available methods

Environment:

This defect, ID QLIK-78874, was resolved in Qlik Sense September 2017.

There are four workarounds to resolve this issue:

• If you have a backup of your certificate you can re-import them following http://help.qlik.com/en-US/sense/June2017/Subsystems/PlanningQlikSenseDeployments/Content/Deployment/Server-Backup-Recovery-Certs-Recovery-Certs.htm
• If you have a backup of the Server and Root certificate you can re-import them and once the Qlik Sense services will be restarted, the QlikClient certificate will be re-created automatically. You can follow this link to re-import the certificate:  following http://help.qlik.com/en-US/sense/June2017/Subsystems/PlanningQlikSenseDeployments/Content/Deployment/Server-Backup-Recovery-Certs-Recovery-Certs.htm
• Before the last option of reinstalling the product, the customer/partner can try repair the sense installation with the initial release. If there are any patches that has been installed, you need to remove the patch before proceeding to repair. 
• If you do not have any backup of the certificates, you will need to uninstall Qlik Sense on the rim node (Keep all options default and do not delete the data) and then reinstall Qlik Sense. It should detect your database and then recreate a new set of certificates.