Installing theme on Nokia N73 phone is the fun activity, but sometime
the users get an error about expired certificate. After this alert
appears then they aren’t able to install the themes anymore.

Expired certificate alert comes on Nokia N73 because it’s according
with security measure of Nokia N-Series operating system that said
installing theme the phone with use it operating system only available
in less than six month.

So, is that mean you are loss all of these great themes offers at N73?
Fortunately not. You are still available to catch those all of them
with a little trick. You need to moving back the date on your Nokia
N-series. On the previous years date you can install theme you want
and change it back to the present date.

Here are below the following steps to change the date on Nokia N73

Under the Menu button there is Tools you can highlight and click OK key
Highlight Settings => OK
Highlight General => OK
Highlight Date and time => OK
Highlight the date => OK
Here you can highlight the year by use the Right navigation key.
Press down navigation key once to change the year back.
Press the red End key to return to standby mode and now you are free
to install the new theme on your N73 cell phone.

In case the expired certificate error still appears, you can change to
another year and install the theme again. If its work back the date
setting to the present through the steps you’re already follow.