Nokia N91 User Manual page 99

In the certificate management main view, you can see a
list of authority certificates that are stored in your device.
Scroll right to see a list of personal certificates, if available.
Digital certificates should be used if you want to connect to
an online bank or another site or remote server for actions
that involve transferring confidential information. They
should also be used if you want to reduce the risk of viruses
or other malicious software and be sure of the authenticity
of software when downloading and installing software.
Important: Even if the use of certificates makes the
risks involved in remote connections and software
installation considerably smaller, they must be used
correctly in order to benefit from increased security.
The existence of a certificate does not offer any
protection by itself; the certificate manager must
contain correct, authentic, or trusted certificates for
increased security to be available. Certificates have
a restricted lifetime. If
Certificate not valid yet
certificate should be valid, check that the current
date and time in your device are correct.
View certificate details—check authenticity
You can only be sure of the correct identity of a server
when the signature and the period of validity of a server
certificate have been checked.
98
Expired certificate or
is shown even if the
You are notified on the device display if the identity of the
server is not authentic or if you do not have the correct
security certificate in your device.
To check certificate details, scroll to a certificate, and select
Options > Certificate details. When you open certificate
details, the validity of the certificate is checked, and one of
the following notes may be displayed:
• Certificate not trusted—You have not set any application
to use the certificate. See "Change the trust settings,"
p. 98.
• Expired certificate—The period of validity has ended
for the selected certificate.
• Certificate not valid yet—The period of validity has
not yet begun for the selected certificate.
• Certificate corrupted—The certificate cannot be used.
Contact the certificate issuer.
Change the trust settings
Before changing any certificate settings, you must make
sure that you really trust the owner of the certificate and
that the certificate really belongs to the listed owner.
Scroll to an authority certificate, and select
Trust settings. Depending on the certificate, a list of the
applications that can use the selected certificate is shown.
For example:
Options >