Error when registering users - There is no certificate in the address book

Whenever I try to register a new user in the last 2 days, I have recived this error

“The administration request could not be created: There is no certificate in the Address Book”

The Person document is created successfully, as is the .ID file. The problem is that the mail file is then not created, and I have to go in and manually set it all up.

Can anyone tell me what this could be?

Subject: Re: User Registration Problem

Does registration report that it completes successfully for the users which receive the certificate error? I question this as the mail file was not generated during the process.

Subject: No, it doesnt

It actually says registration failed or incomplete.When I go into the log it shows the reported error.