How do you change the phone data on my cellphone?

My phone is Nokia N81. Some theme I tried to installed said, %26quot;Certificate Expired%26quot; so someone said that I should change phone data on my phone from 2007 to 2006, then install theme and then come back to 2007. The thing is, I don't know how to change the phone data. Can someone please tell me and list the instructions?



Thanks, I really appreciate it.How do you change the phone data on my cellphone?
about %26quot;Certificate Expired%26quot; query-

go to application manager option in your menu.(it would be somewhere in settings and near file manager or data manager option.)

In Application manager go to options then into settings then-

there Will l be option - Software installation-change it to %26quot;ALL%26quot;.

below there will be option like- Online certificate check- change it to -%26quot;NO%26quot;.

its all done.

Now there will be no %26quot;Certificate Expired%26quot; problem.

but still if it is so, then use this- change your phone date on my phone from 2007 to 2006(Mind it, it is change phone's %26quot;DATE%26quot; to 2006 not phone's DATA)

for this.. simply go to your clock settings then into options and there change the date to 2006.

now install that application or theme and after installation change the date to current date.

Simple.

Do it.How do you change the phone data on my cellphone?
i would try calling customer service, they will talk you through it, best of luck blue