Hi Shamper and Eric, thanks for your responses.
I tried to wipe out the iPhone 4 which took quite a lot of effort (I can't use Apple configurator 2 on my 2009 MacBook Pro because it runs on 10.11.6 El Capitan, not suitable for the configurator). I succeeded after several trials to force a re-init (not sure it was the proper one because the screen did not show as on the instructions). I went for the "naked" version i.e. without my installed apps.
It reloaded (it included my complete address book). However, it does not accept my Apple pwd :
- when going to the AppStore, it requests a validation code for Apple id.
- On my iPhone6S I receive a request of authorization for a new device.
- I accept and receive a 6-digit code.
- I go to the iPh4, enter my Apple id pwd but it is rejected (I even tried to concatenate pt pwd and the 6-digit code) and I'm back in the loop (request to authorize…) I never see a panel where I can enter the 6-digit code.
- Other than that, the iPh4 connects OK to the Internet (via WiFi). Not to the AppStore of course but that's because of the pwd issue.
Is there anything else I can try ?
Thanks for any help.