Certificate has is expired or not yet valid - by: Giuseppe12

Since two weeks in Visual Studio 2017 develop I receive this exception when run SubscribeEvent.Subscribe()

“Errore comunicazione : OPC-UA service result - Certificate has is expired or not yet valid. NotTimeValid: Un certificato richiesto non rientra nel suo periodo di validità se verificato rispetto all'ora corrente del sistema o al timestamp sul file firmato = BadCertificateTimeInvalid.
---- SERVICE RESULT ----
Status Code: {BadCertificateTimeInvalid} = 0x80140000 (2148794368)
-=-=-Description: Certificate has is expired or not yet valid. NotTimeValid: Un certificato richiesto non rientra nel suo periodo di validità se verificato rispetto all'ora corrente del sistema o al timestamp sul file firmato
Additional Info: <ExceptionTrace>
+ The SDK action called was "ApplicationInstance.CheckApplicationInstanceCertificate".
+ Following (9) events were gathered during the action on activity ID [22], in the order of first occurrence:
SDK trace: Checking application instance certificate.
SDK trace: Checking application instance certificate. CN=PaperFreeCutService
4*Exception: {Opc.Ua.ServiceResultException} Certificate has is expired or not yet valid. NotTimeValid: Un certificato richiesto non rientra nel suo periodo di validità se verificato rispetto all'ora corrente del sistema o al timestamp sul file firmato
SDK trace: Cert Validate failed: BadCertificateTimeInvalid
SDK trace: Certificate 'CN=PaperFreeCutService' rejected. Reason=BadCertificateTimeInvalid
SDK trace: Writing rejected certificate to directory: [Directory]%LocalFolder%/OPC Foundation/CertificateStores/RejectedCertificates
+ The error occurred while creating or checking the (client) application instance certificate. Check event log entries for errors and warnings.
+ This is an engine-level error.“

but we bought QuickOPC permanent key.

What happens ? What changed ?

Thanks