Unknown error code 1671

Hi FredJoann,

I'm sorry to hear you are having this issue with your iPhone. I also apologize, I'm a bit unclear on exactly what you are asking or describing, or in what context you are seeing this error message. Based on the number range of the error, if you are seeing this error while attempting to update or restore your iPhone, you may find the information and steps outlined in the following article helpful:

Resolve iOS update and restore errors in iTunes - Apple Support

Cheers