Select > Settings and Connectivity > Settings > VPN .
You need a virtual private network (VPN) connection to, for example, browse your company intranet or access your work mail remotely.
VPN policies define how data is encrypted and how your company authenticates your phone. To configure the VPN client, certificates, and policies, contact your company's IT department. After installing a policy, a VPN connection method is automatically added to an intranet destination.
For more info, search for mobile VPN at www.nokia.com/support .
The existence of a certificate considerably reduces risks involved in remote connections and software installation. To benefit from increased security, certificates must be used correctly, and they must be correct, authentic, or trusted. Certificates have a restricted lifetime. If they have expired or are invalid, check that the current date and time in your device are correct.
Before modifying any certificate settings, you must trust the owner of the certificate and that the certificate does belong to the listed owner.