Sometimes when we download and install themes and games, we get the dreaded certificate error, which is one of the most annoying errors to ever be seen on a Nokia N8 device and is caused by a lack of a security certificate. If a game has a signed certificate and this certificate has expired, we generally see this type of error occur – however there’s a way to ‘fix’ this problem which is useful especially if you particularly like the application/game/theme that is displaying the error.
All mobile phones that run on the Symbian^3 software, such as the Nokia N8, require an installation file to be signed with a Symbian certificate that is designed for the particular phone that the installation is created for. We will help you through the .sis and .sisx signing process.
Requesting Symbian Certificate
You need to request a Symbian certificate at this website; http://cer.opda.cn/EN/. Simply create a free account and request for a certificate for several mobile phones. Once you have actually registered on the website you need to go to the ‘My Certificate’ section of the website and click on the ‘Apply Cer’ button. On the next screen you will have to provide the details that the form requests and it also requires your phone IMEI number. If you need to find your IMEI number simply tap in *#06# on to your phone and the number will be displayed. It takes between twelve and fourty-eight hours for the certificate to be generated, which is slightly annoying but not the end of the world – it gives you the ability to sign .sis and .sisx files for your Nokia N8. After the aforementioned time has elapsed, visit the ‘My Certificate’ section of the website again and you should now see a .cer and .key link under the ‘Operate’ column of the page. We need the two files that were generated, namely the xyz.cer and xyz.key, which are used as explained in the next portion of the guide – download these two files and save it to your computer.
Signing .SIS and .SISX files
To sign .sis and .sisx files for your Nokia N8 you will need an application called XSign to sign the files. The application has three fields where you need to locate the signsis.exe (this is required to process the unsigned file), ‘YourPhoneCertificate.cer’ (Certificate File)
and ‘YourPhoneKey.key’ (Key File) files. You should leave the Key Password field blank and then drag and drop any unsigned files in the File Signing Lists part of the XSign application. There are plus (+) and minus (-) button with which you can add or removed any unsigned files you wish.
The ability to sign multiple .sis and .sisx files at any given time is a great function, as a lot of people often download many themes at a time and a lot of them oftentimes have an expired certificate error. After completing all of the above steps you will now need to click ‘Start’ and a pop-up will then be displayed explaining the status of the signed files. Click ‘OK’ and then you should see the folder containing the signed file open – now that’s done simply transfer your file using Mass Storage Mode on the Nokia N8 or use Nokia’s Ovi Suite to install the application.
The download link as below contains two files which you will need – XSign Setup and SignSIS.exe files. The software has been tried and tested on Windows Vista and should too work on Windows 7, however if you have any problems with the installation or running of it try running the application in compatibility mode.