Expired Certificate error on Nokia 5800

[taher]

Hi,
I am facing a strange problem with nokia 5800 phone. when i try to install sis file on my 5800. I get an "Expired certificate" error, but I've checked and double checked the dates on the phone and my PC, and it's not expired! It's not even close to expiring. I tried creating a new certificate valid from today, it still fails. I've tried the usual trick of changing the phone date forward and backwards with no success, except that setting it back usually produces the expected "Certificate not yet valid" error instead.

Is this actually a problem with the phone software ?

Thank you

[Simond]

The Bug is already fixed and will be deployed with the next firmware update. Until then the solution is to reset the phone (*#7370#) and make sure that you have a valid SIM card inside and network coverage at the time you type in the correct country and date/time information.

[Gonzo]

This happens probably because of new Symbian S60 5th Edition software running on Nokia 5800. On some user forums people find a solution to solve this issue.

The main action you have to do is to reset your phone's software to manufacturer state via key sequence *#7370#. Device ask you to enter lock code, it should be 12345. But you can backup all your data before this action with Nokia PC Suite and restore it after resetting software.
Also it's better to update phone's firmware to latest version (to check version number press *#0000#) because in older versions you may still got "Expired certificate" error message sometimes later.