Hi @nanane76, let me see if i can help you out here.
I have translated your question to English as this is an International forum, please post any replies in English and it will be easier for me and other users to assist you.
Could you please elaborate in a matter of which type of code you mean? Is it a code for unlocking the network so you could use which operator you want? Or is it a screen lock code that you can't remember?
If it is a code for unlocking the network, do you get any kind of errormessages? Or more exactly, what happens when you are trying to do it?
If it is a screen lock that you can't remember, you will be needed to perform a software repair using Xperia Companion. This procedure will erase all data on your internal memory, and if you can't remember your code for unlocking the phone you can't backup any data i'm sorry to say.
Please get back to me with more information if needed or just with how it went.
