Error processing certificate

Error in the Notes log file:

10/09/2006 01:00:00 PM Error processing certificate created by /OU1/OU2/COMPANY for NAME/OU1/OU2/COMPANY: Your certificate has expired

Can anyone help me to realise what it is about? What makes it even more mysterious that the person is no longer exists in the Address book, but some process is running and every 10 minutes tries to process the certificate… Please help to understand what task it is and how to stop it for this user.

Thank you!

Subject: Error processing certificate

Try looking under Certificate\ Notes Cross Certificates and see if it’s there.

If it is you should be able to simply delete the cross certificate, but take a backup of names.nsf first to be careful

Subject: Thanks , but the name is not there…

Other ideas or places to look at?