You can’t connect to a Wi-Fi directly if it’s SSID has any non-ASCII characters on Raspbian in GUI mode. For example, if your Wi-Fi is called 素晴らしいチンチンもの, you can convert it to hex string with Python:

'素晴らしいチンチンもの'.encode('utf-8').hex()

then copy this hex string to /etc/wpa_supplicant/wpa_supplicant.conf without the quotation mark.

Or

You can simply type the SSID to /boot/wpa_supplicant.conf inside the quotation marks, it works. I have tried this before but didn’t notice it failed because the SD card was dead.

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