hello Erel, thanks for your answer
i have created a new certificat and provisioning profile, with a new identifier, i have updated my keys folder with the new ones, and i still have this problem :
error: private Missing private key for signing certificate. Failed to locate the p key matching certificate "iPhone Developer: Zoubair Chaachouh (2F74XW5ZQU)" in the keychain. To sign with this signing certificate, install its private key in your keychain. If you don't have the private key, select a different signing certificate for CODE_SIGN_IDENTITY in the build settings editor. (in target 'B4iProject')
how do i get the private key for the new certificate ? where should i enter it ?