Try setting the date back on your phone 2 years and try again.
Also, there is further information regards to this here.
Hope this helps,
Note that there are multiple digital certificates on Nokia phones for different purposes (code signing certificates for applications, TLS/SSL certificates for secure web or email access, etc.)
And from the original post it is hard to determine what the issue really is; a missing/deleted certificate, or an expired certificate.
Setting the time back only helps, if this about an expired certificate, but not if it is about a missing/deleted certificate.
Restoring firmware-supplied certificates is only possible by reinstalling the firmware.
I would like to clarify if you receive a "Certificate error" during installation of Nokia Store application.
This error generally occurs due to the certificate is out of sync. User can update the device firmware to get the latest certificates. Set the device date and time to the current then download and install the application.
You need to use Nokia Suite to check for updates.
Go to the link below for possible solution to your problem.
2013-03-18 14:36 - edited 2013-03-18 14:38
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