Moving Blog to a new domain on a new server

I copied all files from the old domain (ancient server) on the new domain on the new server. I created a new Mysql on the new server, changed the data of the new database in wp-config.php. Imported the data from the old database and changed some data in the imported database (ex. new name).
I can access the blog alright at https://blog-defis-de-lhumanite.org but when I try to login in my admin module I have this answer :

Warning: Cannot modify header information – headers already sent by (output started at /home/blogdycm/public_html/wp-config.php:169) in /home/blogdycm/public_html/wp-login.php on line 337

Warning: Cannot modify header information – headers already sent by (output started at /home/blogdycm/public_html/wp-config.php:169) in /home/blogdycm/public_html/wp-login.php on line 349

Warning: Cannot modify header information – headers already sent by (output started at /home/blogdycm/public_html/wp-config.php:169) in /home/blogdycm/public_html/wp-login.php on line 351

Also on the page the password is not accepted.

nitram