Many users are reporting that after updating to Belle on their Nokia N8 devices, a security code appears which the user didn’t set. Although you can enter any password to go through it, this bug has yet no stable solution to it by Nokia Support. Users at Nokia Discussion are mentioning many solutions, but still Nokia has not given a proper response to this after the continuous reports about this.
In the previous article, if you read the Belle FAQ, then you would’ve noticed that Nokia mentions that the security code will disappear after a couple of times but it doesn’t.
For my case, I can enter any code each time, then I can use my Nokia N8 without any issues. An app that Belle brought, F-Secure: I personally advise removing it because while I had Anna, it would present me with similar problems. After a couple of tests, the F-Secure code that you use, does work sometimes.
I tried most solutions that could be found on Nokia Discussion, the answer to this issue that I do recommend is: press the power button, and lock the phone, it will ask for the security code and not a new security code, ignore that and wait till it prompts for a new code, after you have configured the code, you can remove it under settings.
Similar to interpreting a text, there are many ways here also for this security code issue, you can also register and configure F-Secure which will then take care of the security code problem.