I didn't it, because i won't dissamble the GPi to connect the keyboard. So i have restored the SD-Card from Backup-File to save time. Now the WiFi works fine. It's a pity that I still don't know what the cause is. I've opened the wpa_supplicant.conf file to see any difference.
country=DE^M
ctrl_interface=DIR=/var/run/wpa_supplicantGROUP=netdev^M
update_config=1^M
network={^M
ssid="NETWORK"^M
psk="PASSWORD"^M
key_mgmt=WPA-PSK^M
priority=1^M
# RETROPIE CONFIG START
network={
ssid="NETWORK"
psk="PASSWORD"
}
# RETROPIE CONFIG END
It seems the same. But, it works. There must be another error.
